Bugzilla – Bug 115317
KDE mute settings have no effect on powerbook pismo
Last modified: 2008-07-16 15:46:57 UTC
this card is muted by default (according to the KDE task bar icon). But muting/unmuting has no effect. Sound works always. 0 [Screamer ]: PMac Screamer - PowerMac Screamer PowerMac Screamer Rev 0 This is on fig.suse.de
I guess it's not only KDE but on others in general? To be sure, run alsamixer and toggle "Master" mute and check whether it works. Does "PC Speaker" switch mute, instead?
the default in alsamixer is 'MM' after startup. toggle on or off makes no difference, aplay /usr/share/sounds/alsa/test.wav always plays the sound.
You meant both "PC Spekaer" and "Master" switches? Then the hardware is incompatible with others...
Created attachment 49020 [details] Patch to ALSA 1.0.10rc1 release
Created attachment 49021 [details] Equivalent patch to SUSE kernel tree
Grr, sorry, a wrong bug. What a great feature of bugzilla to show the next bug...
Could you check comment #3? snd-powermac driver has "Master" and "PC Speaker" mixer switches. They can be controlled manually on alsamixer, too.
yes, the "PC Speaker" mute toggle disables sound. "PC Speaker" volume is zero per default, but sound works anyway. Tge "Master" mute toggle has no effect, at least for console beep.
The "Master" usually controls the line-out jack while the "PC Speaker" does the built-in speaker on powermac driver.
same on my G4, must be local to screamer.
Could you check the status of "Headphone Detection" and "Auto Mute Switch" on mixer? At easiest, you can run like "alsactl -f somefile store" and see that file. The "Headphone" and "PC Speaker" switches are automatically turned on/off according to the line plug status, if "Auto Mute Switch" is ON. The current jack plug status is shown in "Headphone Detection" element. Possibly, the jack detection doesn't work well on these machines.
Created attachment 50919 [details] /tmp/nectarine.alsactrl.mute.txt
And how is the physical connection? Is any jack connected to line-out? If no jack is connected, it isn't really a bug. The "Master" switch must be off because of auto-mute feature. "PC Speaker" is turned on, instead, unless you override the state via alsactl. It's a bad desgin, I admit, though. We'll need some rewrites for better usability...
there are no speakers connected. is this specific to alsa, would it work better with oss dmasound_pmac. If so, how do I test it?
Again, it's not a bug but a design issue. The chip has no master volume control but independent controls to the line-out jack and the internal speaker. On ALSA, they are mapped to "Master" and "PC Speaker", respectively. Unfortunately, these controls are misleading for OSS-style mapping, and it confuses kmix. So, basically it doesn't matter what kmix shows in the applet. It shows only the Master mute, but not pc-speaker mute. Now another problem is that these switches can be overridden by alsactl, too, although they are toggled automatically according to the line jack state. To get the sane state, just toggle off and on "Auto Mute Switch". This will reset the mute switches on master and pc-speaker according to the current line jack state. In short: I won't fix this bug for SL10.0. It's a driver feature. The behavior might be improved in the next version.