[LAU] Many identical cards - how to keep them straight

[drew Roberts]

On Sunday 09 March 2008 18:44:21 Mark Knecht wrote:
> Hi,
>    I'm aware of and use standard Alsa methods to keep different sound
> cards in the same system straight as far as Alsa is concerned. I'm
> wondering what the proper process would be to keep 3 HDSP9652's which
> are physically in the same system, or multiple USB sound devices
> external to the system, straight as far as Alsa is concerned. I'd like
> to know that a certain card always will be always be card 0, card 1 or
> card 2. I do not want Alsa or Linux to make this decision for me and I
> certainly don't want Alsa to change them from boot cycle to boot
> cycle.
>
>    What's the process to determine which identical card is which? Do
> you need to determine some sort of card specific hardware ID and then
> write udev rules or is there some way to do this within Alsa?

I needed to solve this problem a while back. The best help I got was telling 
me it was not possible.

I would be very interested to learn that there is a way. I got a lot of info 
that would help with non-identical cards though.
>
> Thanks,
> Mark

all the best,

drew