Sound related hot keys not working

Cameron Hutchison camh at
Fri Jun 16 07:06:23 UTC 2006

I'm following up to my earlier post to provide the answers to the
problems I have raised. I've had a bit of help and done some
investigating and wanted to share my results with the list in case other
people are having similar problems.

>Issue #1: Volmue up/down and mute do not work fully. 

This was caused by separate controls for the Master volume and the
Headphone volume. It was fixed by putting the following line in the file
/etc/modprobe.d/local-laptop-volume :
options snd-intel8x0 ac97_quirk=hp_only

That unified the Master and Headphones volume control into a single
Master volume control.

>Issue #2: Volume up does not work at all. 

This was caused by having the gconf key
/apps/gnome_setting_daemon/volume_step set to 3 (which is interpretted
as 3 percentage points). As the underlying volume control supported
values from 0 to 31, one step is slightly more than three percentage
points. The gnome-settings-daemon code was rounding down the result
meaning the volume up when nowhere. Volume down worked, because it also
was rounded down.

By setting the gconf key to zero, gnome-settings-daemon used a default
volume step of 6.

There's still an issue in that the volume goes down faster than it goes
up, because it is rounding all values down (truncating when converting
from a double to an int), but at least I can change the volume now.

>Issue #3: Play/Pause behaviour is really strange. 
>Issue #4: Stop, Prev and Next do not work consistently in rhythmbox.

I still do not completely understand everything that was going on here,
but the issue was fixed by putting the following four lines in my
$HOME/.Xmodmap file:
keycode 129 =
keycode 130 =
keycode 131 =
keycode 132 =

Play, Stop, Prev and Next had two mappings to different keycodes. Those
above were incorrect (ie. by running xev(1), I saw what the actual
keycode that was generated by the keypresses - it wasn't those above).

It now doesn't matter if the corresponding actions in
System->Preferences->Keyboard Shortcuts are configured or disabled,
since in both cases the keymap is set up properly.

I dont see why mapping two keycodes to the one keysym should stop it
working - rhythmbox should see the keysym and act accordingly - but it
dont so it broke.

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