Volumio 3 on Odroid N2+ with Motu M2 - no audio

Hello,

I’m running Volumio 3.417 on an Odroid N2+ board with kernel 4.9.241+.
I’ve connected my USB Motu M2 audio interface which gets recognized by the OS and Volumio. However on playback no sound comes out of the device.

Playback options:
Output Device: M2
DSD Playback mode: DSD Direct
Mixer type: none (tried with software too with same results)
Audio Resampling: off

During playback:

-bash-5.0# cat /proc/asound/card1/stream0
MOTU M2 at usb-xhci-hcd.0.auto-1.3, high speed : USB Audio

Playback:
  Status: Running
    Interface = 1
    Altset = 1
    Packet Size = 56
    Momentary freq = 44100 Hz (0x5.8333)
  Interface 1
    Altset 1
    Format: S32_LE
    Channels: 2
    Endpoint: 2 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: 3 IN (ASYNC)
    Rates: 44100, 48000, 88200, 96000, 176400, 192000
    Data packet interval: 125 us
-bash-5.0#

Any advice on how I can troubleshoot this further? The same device works fine when connected to a macbook.

Thanks!
Gabriele

Odroid N2 uses a kernel which does not support the Motu M2 USB audio device. There is nothing you can do to enable it.
Odroid N2 will not be developed any further, just new images with the existing kernel.

That’s unfortunate :frowning:

I’ve tried using the x86 image on a qemu VM on another system, with USB pass-through and I run into the same issue:
kernel: Linux audiobox 5.10.139-volumio #1 SMP Tue Aug 30 15:09:12 CEST 2022 x86_64 GNU/Linux
During playback with no audio coming out:

-bash-5.0# cat /proc/asound/M2/stream0
MOTU M2 at usb-0000:02:1b.0-1, high speed : USB Audio

Playback:
  Status: Running
    Interface = 1
    Altset = 1
    Packet Size = 72
    Momentary freq = 44100 Hz (0x5.8333)
  Interface 1
    Altset 1
    Format: S32_LE
    Channels: 2
    Endpoint: 2 OUT (ASYNC)
    Rates: 44100, 48000, 88200, 96000, 176400, 192000
    Data packet interval: 125 us
    Bits: 24
    Channel map: FL FR

Capture:
  Status: Stop
  Interface 2
    Altset 1
    Format: S32_LE
    Channels: 2
    Endpoint: 3 IN (ASYNC)
    Rates: 44100, 48000, 88200, 96000, 176400, 192000
    Data packet interval: 125 us
    Bits: 24
    Channel map: FL FR
-bash-5.0#

Is the combination Volumio + Motu M2 supposed to work at all? As far as I can tell it should but I have limited knowledge of audio on Linux.
Thanks!

What kind of USB cable are you using. The default shipped USB cable doesn’t seems to work with Linux.
There are many reported issues with this DAC running on Linux, related to the USB cable.
this cable has been reported to work.

VM’s are not supported with Volumio. First try to get the DAC up and running the normal way. If that succeeded, you can play around with VM’s. (not advised with this DAC)
Download the x86 image, flash it to a USB and boot your PC from it and see if it works. It see reports that it works with Kernel > 5.10

My advice: google a bit and you will see you have a problematic device in your hands. There are plenty of issue reports, from no audio to glitches and hanging after a while. There are a number of usb quirks for the audio driver, which are meant to make this device perform better, but only implemented in newer kernels and people still report problems.
I would get rid of it and look for something that is known to work.

Thank you both for the replies :slight_smile:

@Wheaten I’ve seen the reported issues regarding the USB cable but I believe not to be affected since the device is detected fine and only the controls don’t seem to be working (wild guess).
I’ll give it a shot, out of curiosity, with booting from a usb drive and see if the DAC works even thought my original intention was to get this running on the N2+, which doesn’t seem to be possible at all.

@gkkpch I naively thought that since the device is class complaint it’d work out of the box, but that seems far from reality. I’ll see if I can find a device which would also work on this old 4.9 kernel as, ideally, I’d like to avoid ditching the N2+ as well.

Wise, it is one of the best boards around and I did add a number of usb audio quirks for known devices to make them DSD direct/raw compatible with N2/N2+. I use it daily with a Khadas Tone2Pro, sometimes connected to my Cambridge DAC 200M.

The Topping E30 II , 125 Euro works like a charm :slight_smile: