I am doing some development on a SiFive Unmatched development board. I need audio out support. Because the board has only one PCI express slot which I intend to use for a VGA, I’ll need to explore the possibility of USB audio.
I am aware that audio via HDMI on Radeons has been met with success for others, but I’d like to first exhaust a standalone USB audio device.
Is anyone aware of any USB audio devices that are known to work, or likely to work, with ALSA?
I am using Ubuntu Server 21.04 with all system updates. I’ve tried ensuring all of the ALSA and PulseAudio related packages are installed.
I would have thought any device using the generic USB audio module would have worked. I see that the snd-usb-audio module is built and appears to load, and yet I still can’t seem to get any sound after I plug a small portable USB speaker.
Plugging in the USB speaker, I saw the following on the bus:
Bus 001 Device 003: ID 1908:2070 GEMBIRD Honk HK-5002 USB Speaker
The kernel logs the following in kern.log:
[ 291.681086] usb 1-2.3: new full-speed USB device number 3 using xhci_hcd
[ 291.850299] usb 1-2.3: New USB device found, idVendor=1908, idProduct=2070, bcdDevice= 1.00
[ 291.850333] usb 1-2.3: New USB device strings: Mfr=1, Product=2, SerialNumber=3
[ 291.850345] usb 1-2.3: Product: USB2.0 Device
[ 291.850355] usb 1-2.3: Manufacturer: Generic
[ 291.850365] usb 1-2.3: SerialNumber: 20130100ph0
[ 292.434209] mc: Linux media interface: v0.10
[ 292.734949] usb 1-2.3: 1:1: cannot get freq at ep 0x2
[ 292.802612] usb 1-2.3: 2:0: bogus dB values (-12800/-12700), disabling dB reporting
[ 292.803733] usbcore: registered new interface driver snd-usb-audio
Yet the device still doesn’t appear to be visible to ALSA:
$ aplay -l
aplay: device_list:276: no soundcards found…
If I try playing an Ogg/Vorbis file with mpv(1), I see the following (but with no sound):
$ mpv “/usr/share/games/lincity-ng/music/default/01 - pronobozo - lincity.ogg”
(+) Audio --aid=1 (vorbis 2ch 44100Hz)
AO: [pulse] 44100Hz stereo 2ch float
A: 00:01:00 / 00:03:30 (28%)
The USB speaker works fine on a Raspberry Pi 4 (arm64) on Ubuntu Server (21.04).