Comment 27 for bug 16454

Hello.

I've been wondering at the same issue on Kubuntu Dapper. Sound output is functional when PCM _or_ master volume is set to 0. Only when _either_ one of these gets muted (from e.g. kmix), does sound output stop.

I'll attach the requested files (with the prefix "1."). "PCM_0" and "master_0" indicate the volume is set to 0 on the indicated channel. Here's the relevant output from 'diff':

$ diff 1.amixer.PCM_0 1.amixer.PCM_0.muted
52,53c52,53
< Front Left: Playback 0 [0%] [on]
< Front Right: Playback 0 [0%] [on]
---
> Front Left: Playback 0 [0%] [off]
> Front Right: Playback 0 [0%] [off]

diff 1.amixer.master_0 1.amixer.master_0.muted
6,7c6,7
< Front Left: Playback 0 [0%] [on]
< Front Right: Playback 0 [0%] [on]
---
> Front Left: Playback 0 [0%] [off]
> Front Right: Playback 0 [0%] [off]

PS. The volume control in alsa acts somewhat strangely. With PCM volume at reasonable levels, the master volume slider doesn't affect the audible volume for roughly half the way from zero upwards. Only when above this threshold, does the audible volume change. Is there a technical (hardware) reason for why this happens? Or is this an issue that would warrant a separate bug report?