Re: Specifying ALSA subdevice

[Volker Rümelin]

> This was asked already a couple of years ago but no solution was found.
>
> I would like to use an ALSA loopback device for my virtual machine. With the now 
> deprecated soundhw/env parameter syntax everything worked. I'm specifying "-device 
> intel-hda -device hda-duplex " which are fine I guess, but the -audiodev parameter 
> is causing trouble:
>
>         -audiodev 
> alsa,id=snd0,out.dev='hw:Loopback,0,4',in.dev='hw:Loopback,1,5'
>
> results in the following error: Invalid parameter '0'
>
> This is logical as comma is the parameter separator. But apparently it cannot 
> be escaped in any way?

Use a double ,, to pass a single , to alsa-lib. In your case this is

-audiodev alsa,id=snd0,out.dev=hw:Loopback,,0,,4,in.dev=hw:Loopback,,1,,5

With best regards,
Volker