[pulseaudio-discuss] multiple users (gnome's switch user) on Ubuntu

[Colin Guthrie]

'Twas brillig, and Brian J. Murrell at 14/04/10 11:21 did gyre and gimble:
> First a general question so that I am not totally OT here... :-)
> 
> In a situation where you have a single physical seat (i.e. one keyboard and 
> monitor) but you might have multiple logical seats (i.e. where one user logs in, 
> then physically "goes away", and a second users logs in on a second X session, 
> without the first user's session being terminated -- although it's idle/unused 
> while the second user is active -- IOW, "switch user" in gnome), is there 
> supposed to be a pulseaudio daemon per user?  That is when multiple logical
> seats are logged in, one PA daemon for each seat?

Yes.

> If yes, when/how in the gnome session process is the per-user PA daemon supposed 
> to be started?  Because as it happens now, on our multi-user machine, only the 
> first seat is getting a PA daemon.

I suspect you could be getting tripped up by a bug.

http://pulseaudio.org/ticket/773

On the first seat, do you have networking enabled? If so, when the
second user's PA tries to start, one of the "default" things is tries
before launching a daemon of it's own is to try and connect via the
network. This connection is allowed but the authentication part fails
(because User 2 is not allowed to access User 1's PA daemon - which is
correct).

However, this process does mean that the autospawn is no longer
attempted. This is fixed in git master, but you can test it quite easily
by simply disabling network support in paprefs.

FWIW, it is started via both the start-pulseaudio-x11 script which in
turn is run via pulseaudio.desktop which is an XDG compliant autostart
entry. Any DE (e.g. gnome, kde etc.) that supports this standard will
run it. Additionally, to deal with non-x11 cases (and when PA crashes!)
it should also autospawn when needed (the afore mentioned bug not
withstanding).

HTHs

Col

-- 

Colin Guthrie
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http://colin.guthr.ie/

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