Support for NUX MG-300 USB interface

[Takashi Iwai]

On Wed, 20 Jan 2021 22:17:35 +0100,
Mike Oliphant wrote:
> 
> I spent a fair bit of time debugging the code setting/getting mixer control
> values, and I can't see anything that seems to be operating incorrectly.

So, even if you unmute and raise both mixers, it didn't help, right?
I took a look at the lsusb output, but I couldn't find anything else
suspicious.

> Unless you have any other suggestions, I'm going to admit defeat and return
> the audio interface.
> 
> It is probably worth committing the clock selector patch - it at least made
> capture work, and it may help with other audio interfaces.

OK, I'll submit two fix patches.


thanks,

Takashi