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
