len at ovenwerks.net
Sun Jul 28 15:05:12 UTC 2013
On Sun, July 28, 2013 2:32 am, Jarno Suni wrote:
> When not using Pulseaudio, muting e.g. Master track by alsamixer or a
> mixer plugin for Xfce does not mute several tracks, which is good.
There are some internal cards where muting the headphones, also mutes
master and the internal speakers... in fact it seems to me muting any one
of the three mutes all three (Intel HDA). Unfortunately, unmuting only
unmutes the one channel... which generally means the master is left muted
when unmuting the the speakers. This is just testing with alsamixer in a
terminal. The xfcealsamixer does not show mutes, but rather mutes any
channel when the slider is moved to the lowest level... so if the user
sets the speaker level to 0 and then raises it there is no sound till they
go and adjust the master as well. I would call that broken.
Pulse on the other hand, just works. It seems to be the best desktop sound
server around. I have found that just unloading the PA-jack bridge,
disables pulse so it causes no problems. It is trivial to set up Alltray
(or similar) to load and upload module-jackdbus-detect just by clicking on
it's systray icon.
Probably the best setup for professional audio where desktop audio gets
used often, is to disable all audio interfaces in pulse (set them to off).
This will set pavucontrol (or equiv.) to not do anything to the alsa
controls but do everything with sw levels when using the the pa-jack
bridge. Then use qasmixer or even just alsamixer to set levels. This may
mean that plugging in headphones on a laptop does not mute the speakers
When set up this way, I have found that while PA does use a bit more CPU,
it is not a problem even on my 10 year old + P4. even using low enough
latency for live use such a guitarix. Unloading module-jackdbus-detect
then takes PA's cpu use to almost nothing and I have never had PA
interfere with anything when set up this way.
I would not recommend using PA with one card and jack with another if
module-jackdbus-detect is loaded. It will cause problems. When using
module-jackdbus-detect PA should have _all_ audio HW turned off.
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