Echo Audio Echo 2 USB Interface

Discussion:

Tristan Chambers

2014-10-11 17:32:27 UTC

I picked up an Echo Audio Echo 2 USB Interface. The product specs list
iPad support through camera connection kit, so I assume it is class
compliant. http://echoaudio.com/blogs/news/6454472-echo-digital-audio-introduces-the-echo-2-usb-audio-interface

However, on most systems when I plug the device in, it shows up in my
sound settings panel under the Input tab, but not under the Output
tab.

Recording works. I can successfully record with arecord -vv -fdat -D
"plughw:CARD=Audio,DEV=0" echo.wav. I also can increase the sample
rate by changing the flags. I verified that the sample rate actually
increases by recording a 50khz test tone into the input and examining
the wave form in an editor. It's there! So this is very promising.
(anyone know of a test to verify bit depth? I want to make sure it's
actually recording at 24bits.)

Playback however, is nothing but trouble. Like I said, the output
device doesn't show up in the Output tab in my sound settings
(gnome/pulse). However, when I list devices and available PCMs with
aplay -l and aplay -L the device shows up on the lists. See specimens
#1, #2, and #3. When I try to play though I get about a 1/4 second of
audio and then nothing, and subsequent attempts to play sound output
nothing. The device then must be unplugged and plugged back in. I'm
playing with the command aplay -vv foo.wav
--device="plughw:CARD=Audio,DEV=0". See output screen on specimen #4.

I installed the latest kernel and had the exact same phenomenon. See
specimen #5.

To move forward here. What kind of debugging tools should I use to
help figure out where the problem is? Any suggestions you have to get
it working?

To be sure that the device is in good working order I hooked it up to
an OSX machine running 10.6.8. Everything works great with no
additional drivers installed, or special configurations.

Tanks for your help,

Tristan

--------------- #1 --------------------

***@ilya:~$ aplay -l
**** List of PLAYBACK Hardware Devices ****
card 0: PCH [HDA Intel PCH], device 0: ALC259 Analog [ALC259 Analog]
Subdevices: 0/1
Subdevice #0: subdevice #0
card 0: PCH [HDA Intel PCH], device 3: HDMI 0 [HDMI 0]
Subdevices: 1/1
Subdevice #0: subdevice #0
card 1: Audio [Echo 2 Audio], device 0: USB Audio [USB Audio]
Subdevices: 1/1
Subdevice #0: subdevice #0

***@ilya:~$ aplay -L
default
Playback/recording through the PulseAudio sound server
sysdefault:CARD=PCH
HDA Intel PCH, ALC259 Analog
Default Audio Device
front:CARD=PCH,DEV=0
HDA Intel PCH, ALC259 Analog
Front speakers
surround40:CARD=PCH,DEV=0
HDA Intel PCH, ALC259 Analog
4.0 Surround output to Front and Rear speakers
surround41:CARD=PCH,DEV=0
HDA Intel PCH, ALC259 Analog
4.1 Surround output to Front, Rear and Subwoofer speakers
surround50:CARD=PCH,DEV=0
HDA Intel PCH, ALC259 Analog
5.0 Surround output to Front, Center and Rear speakers
surround51:CARD=PCH,DEV=0
HDA Intel PCH, ALC259 Analog
5.1 Surround output to Front, Center, Rear and Subwoofer speakers
surround71:CARD=PCH,DEV=0
HDA Intel PCH, ALC259 Analog
7.1 Surround output to Front, Center, Side, Rear and Woofer speakers
hdmi:CARD=PCH,DEV=0
HDA Intel PCH, HDMI 0
HDMI Audio Output
dmix:CARD=PCH,DEV=0
HDA Intel PCH, ALC259 Analog
Direct sample mixing device
dmix:CARD=PCH,DEV=3
HDA Intel PCH, HDMI 0
Direct sample mixing device
dsnoop:CARD=PCH,DEV=0
HDA Intel PCH, ALC259 Analog
Direct sample snooping device
dsnoop:CARD=PCH,DEV=3
HDA Intel PCH, HDMI 0
Direct sample snooping device
hw:CARD=PCH,DEV=0
HDA Intel PCH, ALC259 Analog
Direct hardware device without any conversions
hw:CARD=PCH,DEV=3
HDA Intel PCH, HDMI 0
Direct hardware device without any conversions
plughw:CARD=PCH,DEV=0
HDA Intel PCH, ALC259 Analog
Hardware device with all software conversions
plughw:CARD=PCH,DEV=3
HDA Intel PCH, HDMI 0
Hardware device with all software conversions
sysdefault:CARD=Audio
Echo 2 Audio, USB Audio
Default Audio Device
front:CARD=Audio,DEV=0
Echo 2 Audio, USB Audio
Front speakers
surround40:CARD=Audio,DEV=0
Echo 2 Audio, USB Audio
4.0 Surround output to Front and Rear speakers
surround41:CARD=Audio,DEV=0
Echo 2 Audio, USB Audio
4.1 Surround output to Front, Rear and Subwoofer speakers
surround50:CARD=Audio,DEV=0
Echo 2 Audio, USB Audio
5.0 Surround output to Front, Center and Rear speakers
surround51:CARD=Audio,DEV=0
Echo 2 Audio, USB Audio
5.1 Surround output to Front, Center, Rear and Subwoofer speakers
surround71:CARD=Audio,DEV=0
Echo 2 Audio, USB Audio
7.1 Surround output to Front, Center, Side, Rear and Woofer speakers
iec958:CARD=Audio,DEV=0
Echo 2 Audio, USB Audio
IEC958 (S/PDIF) Digital Audio Output
dmix:CARD=Audio,DEV=0
Echo 2 Audio, USB Audio
Direct sample mixing device
dsnoop:CARD=Audio,DEV=0
Echo 2 Audio, USB Audio
Direct sample snooping device
hw:CARD=Audio,DEV=0
Echo 2 Audio, USB Audio
Direct hardware device without any conversions
plughw:CARD=Audio,DEV=0
Echo 2 Audio, USB Audio
Hardware device with all software conversions

--------------- #2 --------------------

***@ilya:~$ arecord -l
**** List of CAPTURE Hardware Devices ****
card 0: PCH [HDA Intel PCH], device 0: ALC259 Analog [ALC259 Analog]
Subdevices: 1/1
Subdevice #0: subdevice #0
card 1: Audio [Echo 2 Audio], device 0: USB Audio [USB Audio]
Subdevices: 1/1
Subdevice #0: subdevice #0

***@ilya:~$ arecord -L
default
Playback/recording through the PulseAudio sound server
sysdefault:CARD=PCH
HDA Intel PCH, ALC259 Analog
Default Audio Device
front:CARD=PCH,DEV=0
HDA Intel PCH, ALC259 Analog
Front speakers
surround40:CARD=PCH,DEV=0
HDA Intel PCH, ALC259 Analog
4.0 Surround output to Front and Rear speakers
surround41:CARD=PCH,DEV=0
HDA Intel PCH, ALC259 Analog
4.1 Surround output to Front, Rear and Subwoofer speakers
surround50:CARD=PCH,DEV=0
HDA Intel PCH, ALC259 Analog
5.0 Surround output to Front, Center and Rear speakers
surround51:CARD=PCH,DEV=0
HDA Intel PCH, ALC259 Analog
5.1 Surround output to Front, Center, Rear and Subwoofer speakers
surround71:CARD=PCH,DEV=0
HDA Intel PCH, ALC259 Analog
7.1 Surround output to Front, Center, Side, Rear and Woofer speakers
dmix:CARD=PCH,DEV=0
HDA Intel PCH, ALC259 Analog
Direct sample mixing device
dsnoop:CARD=PCH,DEV=0
HDA Intel PCH, ALC259 Analog
Direct sample snooping device
hw:CARD=PCH,DEV=0
HDA Intel PCH, ALC259 Analog
Direct hardware device without any conversions
plughw:CARD=PCH,DEV=0
HDA Intel PCH, ALC259 Analog
Hardware device with all software conversions
sysdefault:CARD=Audio
Echo 2 Audio, USB Audio
Default Audio Device
front:CARD=Audio,DEV=0
Echo 2 Audio, USB Audio
Front speakers
surround40:CARD=Audio,DEV=0
Echo 2 Audio, USB Audio
4.0 Surround output to Front and Rear speakers
surround41:CARD=Audio,DEV=0
Echo 2 Audio, USB Audio
4.1 Surround output to Front, Rear and Subwoofer speakers
surround50:CARD=Audio,DEV=0
Echo 2 Audio, USB Audio
5.0 Surround output to Front, Center and Rear speakers
surround51:CARD=Audio,DEV=0
Echo 2 Audio, USB Audio
5.1 Surround output to Front, Center, Rear and Subwoofer speakers
surround71:CARD=Audio,DEV=0
Echo 2 Audio, USB Audio
7.1 Surround output to Front, Center, Side, Rear and Woofer speakers
iec958:CARD=Audio,DEV=0
Echo 2 Audio, USB Audio
IEC958 (S/PDIF) Digital Audio Output
dmix:CARD=Audio,DEV=0
Echo 2 Audio, USB Audio
Direct sample mixing device
dsnoop:CARD=Audio,DEV=0
Echo 2 Audio, USB Audio
Direct sample snooping device
hw:CARD=Audio,DEV=0
Echo 2 Audio, USB Audio
Direct hardware device without any conversions
plughw:CARD=Audio,DEV=0
Echo 2 Audio, USB Audio
Hardware device with all software conversions

---------------- #3 -------------------

***@ilya:/proc/asound/card1$ cat stream0
ECHO Digital Audio Echo 2 Audio at usb-0000:00:14.0-1, high speed : USB Audio

Playback:
Status: Stop
Interface 1
Altset 1
Format: S32_LE
Channels: 4
Endpoint: 1 OUT (ASYNC)
Rates: 44100, 48000, 88200, 96000, 176400, 192000
Data packet interval: 125 us

Capture:
Status: Stop
Interface 2
Altset 1
Format: S32_LE
Channels: 2
Endpoint: 2 IN (ASYNC)
Rates: 44100, 48000, 88200, 96000, 176400, 192000
Data packet interval: 125 us

------------------- #4 ------------------

aplay -vv foo.wav --device="plughw:CARD=Audio,DEV=0"

Its setup is:
stream : PLAYBACK
access : MMAP_INTERLEAVED
format : S32_LE
subformat : STD
channels : 4
rate : 48000
exact rate : 48000 (48000/1)
msbits : 32
buffer_size : 24000
period_size : 6000
period_time : 125000
tstamp_mode : NONE
period_step : 1
avail_min : 6000
period_event : 0
start_threshold : 24000
stop_threshold : 24000
silence_threshold: 0
silence_size : 0
boundary : 1572864000
appl_ptr : 0
hw_ptr : 0
############+ | 23%

------------------- #5 ------------------

***@ilya:~$ uname -a
Linux ilya 3.17.0-031700-lowlatency #201410060605 SMP PREEMPT Mon Oct
6 11:06:16 UTC 2014 i686 i686 i686 GNU/Linux
***@ilya:~$ cat /proc/asound/version
Advanced Linux Sound Architecture Driver Version k3.17.0-031700-lowlatency.

Daniel Mack

2014-10-13 14:45:52 UTC

Permalink

Hi,

Post by Tristan Chambers
I picked up an Echo Audio Echo 2 USB Interface. The product specs list
iPad support through camera connection kit, so I assume it is class
compliant. http://echoaudio.com/blogs/news/6454472-echo-digital-audio-introduces-the-echo-2-usb-audio-interface
However, on most systems when I plug the device in, it shows up in my
sound settings panel under the Input tab, but not under the Output
tab.
Recording works. I can successfully record with arecord -vv -fdat -D
"plughw:CARD=Audio,DEV=0" echo.wav. I also can increase the sample
rate by changing the flags. I verified that the sample rate actually
increases by recording a 50khz test tone into the input and examining
the wave form in an editor. It's there! So this is very promising.
(anyone know of a test to verify bit depth? I want to make sure it's
actually recording at 24bits.)
Playback however, is nothing but trouble. Like I said, the output
device doesn't show up in the Output tab in my sound settings
(gnome/pulse). However, when I list devices and available PCMs with
aplay -l and aplay -L the device shows up on the lists. See specimens
#1, #2, and #3. When I try to play though I get about a 1/4 second of
audio and then nothing, and subsequent attempts to play sound output
nothing. The device then must be unplugged and plugged back in. I'm
playing with the command aplay -vv foo.wav
--device="plughw:CARD=Audio,DEV=0". See output screen on specimen #4.

Any messages in dmesg when you try this? And does PulseAudio generate
any logs that look suspicious? The output of 'lsusb -v' might also be
helpful.

Daniel

Tristan Chambers

2014-10-23 03:16:53 UTC

Permalink

Silly me, I tried it in a USB 2 port and now I'm getting much better
results. I guess there are problems with this device on a USB 3 port
in Linux - or maybe in general? There are still several problems
though. Now I can get it to record and play with arecord and aplay,
and I can run Jack and Ardour or Audacity with jack selected and do
multitrack recording no problem! HOWEVER, the playback device still
doesn't show up in my Gnome/Pulse manager. Also when I open Audacity
(no jack) the device shows up on the list of ALSA devices but when I
select the device for input or output the device emits several audible
clicks, and when I try to record or play the program either crashes or
goes very very slow and can only play or capture a fraction of a
second worth of data.

Regarding your suggestions, I see very little reported in dmesg. I'm
unaware of separate logs for PulseAudio. Anyone else have any ideas?
It would be convenient, but not critical to get it working like any
other sound device.

Anybody have any ideas for better debugging of the issue? I'd say the
current state is livable but maybe not something I'd say 'works for
anyone.'

------ dmesg -------

[ 137.058345] usb 3-1: new high-speed USB device number 2 using xhci_hcd
[ 137.222869] usb 3-1: New USB device found, idVendor=040f, idProduct=0010
[ 137.222873] usb 3-1: New USB device strings: Mfr=1, Product=2, SerialNumber=3
[ 137.222875] usb 3-1: Product: Echo 2 Audio
[ 137.222877] usb 3-1: Manufacturer: ECHO Digital Audio
[ 137.222878] usb 3-1: SerialNumber: 0000
[ 139.452978] usbcore: registered new interface driver snd-usb-audio
[ 140.110495] retire_capture_urb: 3 callbacks suppressed

------ lsusb -v ------

***@ilya:/var/log$ lsusb -v

Bus 002 Device 004: ID 040f:0010 Echo Speech Corp.
Couldn't open device, some information will be missing
Device Descriptor:
bLength 18
bDescriptorType 1
bcdUSB 2.00
bDeviceClass 239 Miscellaneous Device
bDeviceSubClass 2 ?
bDeviceProtocol 1 Interface Association
bMaxPacketSize0 64
idVendor 0x040f Echo Speech Corp.
idProduct 0x0010
bcdDevice 0.38
iManufacturer 1
iProduct 2
iSerial 3
bNumConfigurations 2
Configuration Descriptor:
bLength 9
bDescriptorType 2
wTotalLength 311
bNumInterfaces 4
bConfigurationValue 1
iConfiguration 0
bmAttributes 0x80
(Bus Powered)
MaxPower 500mA
Interface Association:
bLength 8
bDescriptorType 11
bFirstInterface 0
bInterfaceCount 3
bFunctionClass 1 Audio
bFunctionSubClass 0
bFunctionProtocol 32
iFunction 0
Interface Descriptor:
bLength 9
bDescriptorType 4
bInterfaceNumber 0
bAlternateSetting 0
bNumEndpoints 1
bInterfaceClass 1 Audio
bInterfaceSubClass 1 Control Device
bInterfaceProtocol 32
iInterface 2
AudioControl Interface Descriptor:
bLength 9
bDescriptorType 36
bDescriptorSubtype 1 (HEADER)
bcdADC 2.00
bCategory 8
wTotalLength 143
bmControl 0x00
AudioControl Interface Descriptor:
bLength 8
bDescriptorType 36
bDescriptorSubtype 10 (CLOCK_SOURCE)
bClockID 41
bmAttributes 0x03 Internal programmable Clock
bmControls 0x07
Clock Frequency Control (read/write)
Clock Validity Control (read-only)
bAssocTerminal 0
iClockSource 9
AudioControl Interface Descriptor:
bLength 8
bDescriptorType 36
bDescriptorSubtype 11 (CLOCK_SELECTOR)
bUnitID 40
bNrInPins 1
baCSourceID( 0) 41
bmControls 0x03
Clock Selector Control (read/write)
iClockSelector 8
AudioControl Interface Descriptor:
bLength 17
bDescriptorType 36
bDescriptorSubtype 2 (INPUT_TERMINAL)
bTerminalID 2
wTerminalType 0x0101 USB Streaming
bAssocTerminal 0
bCSourceID 40
bNrChannels 4
bmChannelConfig 0x00000000
bmControls 0x0000
iChannelNames 15
iTerminal 6
AudioControl Interface Descriptor:
bLength 26
bDescriptorType 36
bDescriptorSubtype 6 (FEATURE_UNIT)
bUnitID 10
bSourceID 2
bmaControls( 0) 0x0000000f
Mute Control (read/write)
Volume Control (read/write)
bmaControls( 1) 0x0000000f
Mute Control (read/write)
Volume Control (read/write)
bmaControls( 2) 0x0000000f
Mute Control (read/write)
Volume Control (read/write)
bmaControls( 3) 0x0000000f
Mute Control (read/write)
Volume Control (read/write)
bmaControls( 4) 0x0000000f
Mute Control (read/write)
Volume Control (read/write)
iFeature 0
AudioControl Interface Descriptor:
bLength 12
bDescriptorType 36
bDescriptorSubtype 3 (OUTPUT_TERMINAL)
bTerminalID 20
wTerminalType 0x0301 Speaker
bAssocTerminal 0
bSourceID 10
bCSourceID 40
bmControls 0x0000
iTerminal 0
AudioControl Interface Descriptor:
bLength 17
bDescriptorType 36
bDescriptorSubtype 2 (INPUT_TERMINAL)
bTerminalID 1
wTerminalType 0x0201 Microphone
bAssocTerminal 0
bCSourceID 40
bNrChannels 2
bmChannelConfig 0x00000000
bmControls 0x0000
iChannelNames 33
iTerminal 0
AudioControl Interface Descriptor:
bLength 18
bDescriptorType 36
bDescriptorSubtype 6 (FEATURE_UNIT)
bUnitID 11
bSourceID 1
bmaControls( 0) 0x0000000f
Mute Control (read/write)
Volume Control (read/write)
bmaControls( 1) 0x0000000f
Mute Control (read/write)
Volume Control (read/write)
bmaControls( 2) 0x0000000f
Mute Control (read/write)
Volume Control (read/write)
iFeature 0
AudioControl Interface Descriptor:
bLength 12
bDescriptorType 36
bDescriptorSubtype 3 (OUTPUT_TERMINAL)
bTerminalID 22
wTerminalType 0x0101 USB Streaming
bAssocTerminal 0
bSourceID 11
bCSourceID 40
bmControls 0x0000
iTerminal 7
Endpoint Descriptor:
bLength 7
bDescriptorType 5
bEndpointAddress 0x84 EP 4 IN
bmAttributes 3
Transfer Type Interrupt
Synch Type None
Usage Type Data
wMaxPacketSize 0x0006 1x 6 bytes
bInterval 8
Interface Descriptor:
bLength 9
bDescriptorType 4
bInterfaceNumber 1
bAlternateSetting 0
bNumEndpoints 0
bInterfaceClass 1 Audio
bInterfaceSubClass 2 Streaming
bInterfaceProtocol 32
iInterface 4
Interface Descriptor:
bLength 9
bDescriptorType 4
bInterfaceNumber 1
bAlternateSetting 1
bNumEndpoints 2
bInterfaceClass 1 Audio
bInterfaceSubClass 2 Streaming
bInterfaceProtocol 32
iInterface 4
AudioStreaming Interface Descriptor:
bLength 16
bDescriptorType 36
bDescriptorSubtype 1 (AS_GENERAL)
bTerminalLink 2
bmControls 0x00
bFormatType 1
bmFormats 0x00000001
PCM
bNrChannels 4
bmChannelConfig 0x00000000
iChannelNames 15
AudioStreaming Interface Descriptor:
bLength 6
bDescriptorType 36
bDescriptorSubtype 2 (FORMAT_TYPE)
bFormatType 1 (FORMAT_TYPE_I)
bSubslotSize 4
bBitResolution 24
Endpoint Descriptor:
bLength 7
bDescriptorType 5
bEndpointAddress 0x01 EP 1 OUT
bmAttributes 5
Transfer Type Isochronous
Synch Type Asynchronous
Usage Type Data
wMaxPacketSize 0x0400 1x 1024 bytes
bInterval 1
AudioControl Endpoint Descriptor:
bLength 8
bDescriptorType 37
bDescriptorSubtype 1 (EP_GENERAL)
bmAttributes 0x00
bmControls 0x00
bLockDelayUnits 2 Decoded PCM samples
wLockDelay 8
Endpoint Descriptor:
bLength 7
bDescriptorType 5
bEndpointAddress 0x81 EP 1 IN
bmAttributes 17
Transfer Type Isochronous
Synch Type None
Usage Type Feedback
wMaxPacketSize 0x0004 1x 4 bytes
bInterval 4
Interface Descriptor:
bLength 9
bDescriptorType 4
bInterfaceNumber 2
bAlternateSetting 0
bNumEndpoints 0
bInterfaceClass 1 Audio
bInterfaceSubClass 2 Streaming
bInterfaceProtocol 32
iInterface 5
Interface Descriptor:
bLength 9
bDescriptorType 4
bInterfaceNumber 2
bAlternateSetting 1
bNumEndpoints 1
bInterfaceClass 1 Audio
bInterfaceSubClass 2 Streaming
bInterfaceProtocol 32
iInterface 5
AudioStreaming Interface Descriptor:
bLength 16
bDescriptorType 36
bDescriptorSubtype 1 (AS_GENERAL)
bTerminalLink 22
bmControls 0x00
bFormatType 1
bmFormats 0x00000001
PCM
bNrChannels 2
bmChannelConfig 0x00000000
iChannelNames 33
AudioStreaming Interface Descriptor:
bLength 6
bDescriptorType 36
bDescriptorSubtype 2 (FORMAT_TYPE)
bFormatType 1 (FORMAT_TYPE_I)
bSubslotSize 4
bBitResolution 24
Endpoint Descriptor:
bLength 7
bDescriptorType 5
bEndpointAddress 0x82 EP 2 IN
bmAttributes 5
Transfer Type Isochronous
Synch Type Asynchronous
Usage Type Data
wMaxPacketSize 0x0400 1x 1024 bytes
bInterval 1
AudioControl Endpoint Descriptor:
bLength 8
bDescriptorType 37
bDescriptorSubtype 1 (EP_GENERAL)
bmAttributes 0x00
bmControls 0x00
bLockDelayUnits 2 Decoded PCM samples
wLockDelay 8
Interface Descriptor:
bLength 9
bDescriptorType 4
bInterfaceNumber 3
bAlternateSetting 0
bNumEndpoints 0
bInterfaceClass 254 Application Specific Interface
bInterfaceSubClass 1 Device Firmware Update
bInterfaceProtocol 1
iInterface 12
Device Firmware Upgrade Interface Descriptor:
bLength 9
bDescriptorType 33
bmAttributes 7
Will Not Detach
Manifestation Tolerant
Upload Supported
Download Supported
wDetachTimeout 250 milliseconds
wTransferSize 64 bytes
bcdDFUVersion 1.10
Warning: Invalid descriptor
Device Firmware Upgrade Interface Descriptor:
bLength 16
bDescriptorType 36
bmAttributes 9
Will Detach
Manifestation Intolerant
Upload Unsupported
Download Supported
wDetachTimeout 226 milliseconds
wTransferSize 256 bytes
bcdDFUVersion 1.02
Configuration Descriptor:
bLength 9
bDescriptorType 2
wTotalLength 311
bNumInterfaces 4
bConfigurationValue 1
iConfiguration 0
bmAttributes 0x80
(Bus Powered)
MaxPower 500mA
Interface Association:
bLength 8
bDescriptorType 11
bFirstInterface 0
bInterfaceCount 3
bFunctionClass 1 Audio
bFunctionSubClass 0
bFunctionProtocol 32
iFunction 0
Interface Descriptor:
bLength 9
bDescriptorType 4
bInterfaceNumber 0
bAlternateSetting 0
bNumEndpoints 1
bInterfaceClass 1 Audio
bInterfaceSubClass 1 Control Device
bInterfaceProtocol 32
iInterface 2
AudioControl Interface Descriptor:
bLength 9
bDescriptorType 36
bDescriptorSubtype 1 (HEADER)
bcdADC 2.00
bCategory 8
wTotalLength 143
bmControl 0x00
AudioControl Interface Descriptor:
bLength 8
bDescriptorType 36
bDescriptorSubtype 10 (CLOCK_SOURCE)
bClockID 41
bmAttributes 0x03 Internal programmable Clock
bmControls 0x07
Clock Frequency Control (read/write)
Clock Validity Control (read-only)
bAssocTerminal 0
iClockSource 9
AudioControl Interface Descriptor:
bLength 8
bDescriptorType 36
bDescriptorSubtype 11 (CLOCK_SELECTOR)
bUnitID 40
bNrInPins 1
baCSourceID( 0) 41
bmControls 0x03
Clock Selector Control (read/write)
iClockSelector 8
AudioControl Interface Descriptor:
bLength 17
bDescriptorType 36
bDescriptorSubtype 2 (INPUT_TERMINAL)
bTerminalID 2
wTerminalType 0x0101 USB Streaming
bAssocTerminal 0
bCSourceID 40
bNrChannels 4
bmChannelConfig 0x00000000
bmControls 0x0000
iChannelNames 15
iTerminal 6
AudioControl Interface Descriptor:
bLength 26
bDescriptorType 36
bDescriptorSubtype 6 (FEATURE_UNIT)
bUnitID 10
bSourceID 2
bmaControls( 0) 0x0000000f
Mute Control (read/write)
Volume Control (read/write)
bmaControls( 1) 0x0000000f
Mute Control (read/write)
Volume Control (read/write)
bmaControls( 2) 0x0000000f
Mute Control (read/write)
Volume Control (read/write)
bmaControls( 3) 0x0000000f
Mute Control (read/write)
Volume Control (read/write)
bmaControls( 4) 0x0000000f
Mute Control (read/write)
Volume Control (read/write)
iFeature 0
AudioControl Interface Descriptor:
bLength 12
bDescriptorType 36
bDescriptorSubtype 3 (OUTPUT_TERMINAL)
bTerminalID 20
wTerminalType 0x0301 Speaker
bAssocTerminal 0
bSourceID 10
bCSourceID 40
bmControls 0x0000
iTerminal 0
AudioControl Interface Descriptor:
bLength 17
bDescriptorType 36
bDescriptorSubtype 2 (INPUT_TERMINAL)
bTerminalID 1
wTerminalType 0x0201 Microphone
bAssocTerminal 0
bCSourceID 40
bNrChannels 2
bmChannelConfig 0x00000000
bmControls 0x0000
iChannelNames 33
iTerminal 0
AudioControl Interface Descriptor:
bLength 18
bDescriptorType 36
bDescriptorSubtype 6 (FEATURE_UNIT)
bUnitID 11
bSourceID 1
bmaControls( 0) 0x0000000f
Mute Control (read/write)
Volume Control (read/write)
bmaControls( 1) 0x0000000f
Mute Control (read/write)
Volume Control (read/write)
bmaControls( 2) 0x0000000f
Mute Control (read/write)
Volume Control (read/write)
iFeature 0
AudioControl Interface Descriptor:
bLength 12
bDescriptorType 36
bDescriptorSubtype 3 (OUTPUT_TERMINAL)
bTerminalID 22
wTerminalType 0x0101 USB Streaming
bAssocTerminal 0
bSourceID 11
bCSourceID 40
bmControls 0x0000
iTerminal 7
Endpoint Descriptor:
bLength 7
bDescriptorType 5
bEndpointAddress 0x84 EP 4 IN
bmAttributes 3
Transfer Type Interrupt
Synch Type None
Usage Type Data
wMaxPacketSize 0x0006 1x 6 bytes
bInterval 8
Interface Descriptor:
bLength 9
bDescriptorType 4
bInterfaceNumber 1
bAlternateSetting 0
bNumEndpoints 0
bInterfaceClass 1 Audio
bInterfaceSubClass 2 Streaming
bInterfaceProtocol 32
iInterface 4
Interface Descriptor:
bLength 9
bDescriptorType 4
bInterfaceNumber 1
bAlternateSetting 1
bNumEndpoints 2
bInterfaceClass 1 Audio
bInterfaceSubClass 2 Streaming
bInterfaceProtocol 32
iInterface 4
AudioStreaming Interface Descriptor:
bLength 16
bDescriptorType 36
bDescriptorSubtype 1 (AS_GENERAL)
bTerminalLink 2
bmControls 0x00
bFormatType 1
bmFormats 0x00000001
PCM
bNrChannels 4
bmChannelConfig 0x00000000
iChannelNames 15
AudioStreaming Interface Descriptor:
bLength 6
bDescriptorType 36
bDescriptorSubtype 2 (FORMAT_TYPE)
bFormatType 1 (FORMAT_TYPE_I)
bSubslotSize 4
bBitResolution 24
Endpoint Descriptor:
bLength 7
bDescriptorType 5
bEndpointAddress 0x01 EP 1 OUT
bmAttributes 5
Transfer Type Isochronous
Synch Type Asynchronous
Usage Type Data
wMaxPacketSize 0x0400 1x 1024 bytes
bInterval 1
AudioControl Endpoint Descriptor:
bLength 8
bDescriptorType 37
bDescriptorSubtype 1 (EP_GENERAL)
bmAttributes 0x00
bmControls 0x00
bLockDelayUnits 2 Decoded PCM samples
wLockDelay 8
Endpoint Descriptor:
bLength 7
bDescriptorType 5
bEndpointAddress 0x81 EP 1 IN
bmAttributes 17
Transfer Type Isochronous
Synch Type None
Usage Type Feedback
wMaxPacketSize 0x0004 1x 4 bytes
bInterval 4
Interface Descriptor:
bLength 9
bDescriptorType 4
bInterfaceNumber 2
bAlternateSetting 0
bNumEndpoints 0
bInterfaceClass 1 Audio
bInterfaceSubClass 2 Streaming
bInterfaceProtocol 32
iInterface 5
Interface Descriptor:
bLength 9
bDescriptorType 4
bInterfaceNumber 2
bAlternateSetting 1
bNumEndpoints 1
bInterfaceClass 1 Audio
bInterfaceSubClass 2 Streaming
bInterfaceProtocol 32
iInterface 5
AudioStreaming Interface Descriptor:
bLength 16
bDescriptorType 36
bDescriptorSubtype 1 (AS_GENERAL)
bTerminalLink 22
bmControls 0x00
bFormatType 1
bmFormats 0x00000001
PCM
bNrChannels 2
bmChannelConfig 0x00000000
iChannelNames 33
AudioStreaming Interface Descriptor:
bLength 6
bDescriptorType 36
bDescriptorSubtype 2 (FORMAT_TYPE)
bFormatType 1 (FORMAT_TYPE_I)
bSubslotSize 4
bBitResolution 24
Endpoint Descriptor:
bLength 7
bDescriptorType 5
bEndpointAddress 0x82 EP 2 IN
bmAttributes 5
Transfer Type Isochronous
Synch Type Asynchronous
Usage Type Data
wMaxPacketSize 0x0400 1x 1024 bytes
bInterval 1
AudioControl Endpoint Descriptor:
bLength 8
bDescriptorType 37
bDescriptorSubtype 1 (EP_GENERAL)
bmAttributes 0x00
bmControls 0x00
bLockDelayUnits 2 Decoded PCM samples
wLockDelay 8
Interface Descriptor:
bLength 9
bDescriptorType 4
bInterfaceNumber 3
bAlternateSetting 0
bNumEndpoints 0
bInterfaceClass 254 Application Specific Interface
bInterfaceSubClass 1 Device Firmware Update
bInterfaceProtocol 1
iInterface 12
Device Firmware Upgrade Interface Descriptor:
bLength 9
bDescriptorType 33
bmAttributes 7
Will Not Detach
Manifestation Tolerant
Upload Supported
Download Supported
wDetachTimeout 250 milliseconds
wTransferSize 64 bytes
bcdDFUVersion 1.10
Warning: Invalid descriptor
Device Firmware Upgrade Interface Descriptor:
bLength 16
bDescriptorType 36
bmAttributes 9
Will Detach
Manifestation Intolerant
Upload Unsupported
Download Supported
wDetachTimeout 226 milliseconds
wTransferSize 256 bytes
bcdDFUVersion 1.02

Post by Daniel Mack
Hi,

Any messages in dmesg when you try this? And does PulseAudio generate
any logs that look suspicious? The output of 'lsusb -v' might also be
helpful.
Daniel