[pulseaudio-discuss] specifying ALSA mixer control

Colin Guthrie gmane at colin.guthr.ie
Fri Mar 27 06:36:56 PDT 2009

'Twas brillig, and Lennart Poettering at 27/03/09 12:45 did gyre and gimble:
> (I) Some hardware/drivers allow you open spdif:0 in app A and front:0
> in app B at the same time and it results in having A's stream come out
> of SPDIF and B's stream coming out Analog.
> (II) Other hardware/drivers however allow you to open spdif:0 in app A
> and front:0 in app B at the same time, and audio is mixed and both
> streams come out of only SPDIF, or only Analog, or even on both. And
> we wouldn't even know which of the cases it actually would be.
> We never want to get confused by case II but we cannot distuingish it
> programmatically from case I. Case I is the one we want to
> support. Case II we want to ignore.

Ahh OK, so the hardware/driver is being too clever then and trying to 
"fail gracefully", but in doing so, it's impossible work out what the 
hell is going on.

IMO, in the short term, it's possibly worth while still probing for 
2-outputs. Yes we may be confused by case 2, but an odd setup (that 
still works in some capacity) for some people is probably worth it 
considering that many others will get a working setup automatically.

But that's just my opinion. Perhaps we can have some kind of switch to 
enable how many outputs to probe which is, by default 1, but can be 
increased? That way we can perhaps expose this via the GUI somehow.



Colin Guthrie

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