ThinkPad T42 mute button does double duty

My T42 used to do what you described, but it seems to have gone to hardware-only at or around the time that I upgraded to the release candidate. Can you upgrade and confirm whether or not this still exists?

Ryan, yes there is currently one use-case that is currently known broken; if you:

  Mute with the hardware-mixer
  Unmute with the software-mixer (this leaves the hardware mixer still muted)

Any other combination of mute, or volume controls should do the Right Thing(tm). Note that on ThinkPads, the hardware mute key *always* mutes and requires a press of the volume up/down keys to unmute it.

Matt: in your bug report, pressing the hardware mute will mute both the hardware and the software mixers; and then pressing the hardware volume-up key will unmute both.

I plan to fix this in edgy with a daemon to synchronise changes in the ALSA mixer status back to the hardware one (mute and volume) and this is the solution also used by MS Windows (for mute only).

The latter will also fix: bug #39098 where the interaction between GNOME un-even volume weighting and the hardware mixer causes issues.

On Sat, May 27, 2006 at 04:10:24PM -0000, Paul Sladen wrote:
> Ryan, yes there is currently one use-case that is currently known
> broken; if you:
>
> Mute with the hardware-mixer
> Unmute with the software-mixer (this leaves the hardware mixer still muted)

This happens also.

> Any other combination of mute, or volume controls should do the Right
> Thing(tm). Note that on ThinkPads, the hardware mute key *always* mutes
> and requires a press of the volume up/down keys to unmute it.
>
> Matt: in your bug report, pressing the hardware mute will mute both the
> hardware and the software mixers; and then pressing the hardware
> volume-up key will unmute both.

On my system:

Pressing the hardware mute mutes both the hardware and software mixers, yes.
Pressing the hardware mute again unmutes ONLY the software mixer.
Pressing the hardware volume keys unmutes ONLY the hardware mixer.

So after muting with the hardware button, I need to press both mute again
AND volume up/down to get sound back (or unmute the software mixer
separately).

--
 - mdz

That's not the behaviour I observe here. What are volume up and volume
down bound to in the gnome keyboard shortcuts?

--
Matthew Garrett | <email address hidden>

On Sat, May 27, 2006 at 04:54:20PM -0000, Matthew Garrett wrote:
> That's not the behaviour I observe here. What are volume up and volume
> down bound to in the gnome keyboard shortcuts?

Both are disabled. Mute is a0, the mute button.

--
 - mdz

I think something must have changed in the GNOME-mixer (gnome-system-tools).
Pressing the mute button once every second leaves the volume muted (as expected), but I note that if I press Mute very fast (eg. > 5 times/second) then about one time in twenty, I can get the 'gnome-mixer' and on-screen display to appear out of sync:

  http://www.paul.sladen.org/ubuntu/bugs/gnome-mixer-mute-out-of-sync.png

There appear to be 5 copies of 'gnome-volume-control' running:

$ lsof +c 0 /dev/snd/controlC*
COMMAND PID USER FD TYPE DEVICE SIZE NODE NAME
mixer_applet2 5291 paul 35u CHR 116,0 9347 /dev/snd/controlC0
gnome-volume-co 11131 paul 14u CHR 116,0 9347 /dev/snd/controlC0
gnome-volume-co 11255 paul 14u CHR 116,0 9347 /dev/snd/controlC0
gnome-volume-co 11735 paul 14u CHR 116,0 9347 /dev/snd/controlC0
totem 11822 paul 27u CHR 116,0 9347 /dev/snd/controlC0
gnome-volume-co 11858 paul 14u CHR 116,0 9347 /dev/snd/controlC0
gnome-volume-co 12219 paul 14u CHR 116,0 9347 /dev/snd/controlC0

To fake the mute action to the software mixer, the thinkpad-keys daemon actually sends KEY_VOLUMEUP, immediately followed by KEY_MUTE; it looks like key-presses maybe getting dropped somewhere.

The output from 'lshal -m' however is correct.

That implies that you've explicitly disabled them at some stage -
they're set in the default schema file, and the only way that would be
overridden is if you've set the value to disabled. If you set them, do
things work more sanely?

--
Matthew Garrett | <email address hidden>

On Sun, May 28, 2006 at 10:49:06AM -0000, Matthew Garrett wrote:
> That implies that you've explicitly disabled them at some stage -
> they're set in the default schema file, and the only way that would be
> overridden is if you've set the value to disabled. If you set them, do
> things work more sanely?

What are they set to by default? I tried to assign them to the hardware
volume up/down keys, but they show the same keycode for both. I don't see
how that would fix the issue with the mute key, though.

--
 - mdz

They ought to be 0xae (down) and 0xb0 (up).

--
Matthew Garrett | <email address hidden>

On Sun, May 28, 2006 at 01:02:30PM -0000, Matthew Garrett wrote:
> They ought to be 0xae (down) and 0xb0 (up).

Odd, it's working now. Yes, that does get it behaving more reasonably.

I think I disabled these some time ago after noticing that they weren't
behaving consistently with regard to the two volume controls, but apparently
it's better now.

Thanks.

--
 - mdz