From: mike scott on
Paul Martin wrote:
> In article <sTEIm.2103$Ym4.1290(a)>,
> mike scott wrote:
>> Can't pretend to truly understand .asoundrc's ins and outs, but I found
>> a good-looking example to edit. So I do have a situation where I can
>> simultaneously play at least two (which is all the speakers I have at
>> the mo') files totally independently using alsaplayer's gui.
> Forget GUIs here! Here's an .asoundrc extract for you.

Thanks for all that. That didn't seem to want to work here as it stood,
so I took the bits about virtual devices and put them into my own
..asoundrc, and it works very nicely -- to a point.

There's no problem while "I'm me". I can get sound from all six
channels. But I created another user account (xyz) for "live" use (whose
only group is 'audio'). It's got an exact copy of my own .asoundrc. Now
weird things happen (I'm using speaker-test) :-

If I boot up and log in as xyz, the front channels remain silent, and I
get sound from the remaining four.

If then log in as myself, I get all six channels; if I log out and log
back in as xyz, I again get just the 4 channels, front ones being
silent. Consistent, at least.

However, if I boot up, log in as me and check the sound (which runs ok),
log out, then log in as xyz and check again, I get errors like "ALSA lib
pcm_dmix.c:975 (snd_pcm_dmix_open) unable to create IPC semaphore",
along with 'Playback open error -13, permission denied'.

Oh, I should be clear that this isn't to do with virtual channels; I'm
checking what in your .asoundrc is labelled pcm.dshare.

Can anyone shed light please?

(There also seem major issues with running under vanilla X, with
messages about dropping root privs, and again channels 0 and 1 won't
work. Presumably related.)

Mike Scott (unet2 <at> [deletethis]
Harlow Essex England