Support for NUX MG-300 USB interface

[Mike Oliphant]

Thanks for the response. I'm running a very recent build of the master
kernel tree (~ 5.11-rc2).

I'll give dyndbg a try.

Mike

On Sun, Jan 17, 2021 at 11:43 PM Takashi Iwai <tiwai at suse.de> wrote:

> On Sun, 17 Jan 2021 19:56:01 +0100,
> Mike Oliphant wrote:
> >
> > I recently got a NUX MG-300 USB guitar fx interface with high hopes that
> it
> > would work in Linux. It is supposed to be class-compliant, and works in
> iOS
> > and macOS without a driver.
> >
> > Unfortunately, while it is recognized as a USB audio device by Linux, it
> is
> > not working.
> >
> > The core issue seems to be that "stream0" reports no playback rates.
> dmesg
> > also shows errors, including "__uac_clock_find_source(): selector
> reported
> > illegal value".
> >
> > Any help identifying the issue would be much appreciated. I have some
> > experience troubleshooting the USB audio kernel code and am happy to try
> > doing so if I can get a nudge in the right direction.
> >
> > Output from "stream0", dmesg, and lsusb follows.
>
> Did you try the latest 5.11-rc kernel?  There have been lots of
> changes in USB-audio and this might work better there.
>
> If it still doesn't work with 5.11-rc, please try to enable the debug
> option, e.g. boot with snd_usb_audio.dyndbg=+p boot option, plug the
> device, and get the kernel logs (at plugging and during the audio
> operations).
>
>
> thanks,
>
> Takashi
>