One should be able to modify the volume when audio is mute
Submitted by Léo Cavaillé
Assigned to pul..@..op.org
Description
Forwarded from : https://bugs.debian.org/732809 Affects latest version 2.0 of pulseaudio, packaged for Debian sid
When "Mute" is selected, the volume sliders (Front Left & Front Right) are greyed out, and it is not possible to modify the volume.
One should be able to modify the volume (in particular lower it) just before unmuting. Otherwise it can be too high, which could be annoying for the neighbors, even during a short period.
See also
Activity
http://freedesktop.org/software/pulseaudio/doxygen/volume.html
The basic volume type in PulseAudio is the pa_volume_t type. Most of the time, applications will use the aggregated pa_cvolume structure that can store the volume of all channels at once.
Volumes commonly span between muted (0%), and normal (100%)
http://freedesktop.org/software/pulseaudio/doxygen/structpa__cvolume.html
seem pulseaudio treat min volume as mute and cannot use the mute switch which is independent of volume control
(In reply to comment 1)
seem pulseaudio treat min volume as mute
No, it doesn't: pavucontrol has separate button for mute and sliders for the volume itself. When the mute is active, pavucontrol is still able to read the volume. So, it should technically be able to modify it.
typedef uint32_t pa_volume_t
Volume specification: PA_VOLUME_MUTED: silence; < PA_VOLUME_NORM: decreased volume; PA_VOLUME_NORM: normal volume;
PA_VOLUME_NORM: increased volume
Sinks, sources, sink inputs and samples can all have their own volumes
the pulseaudio internal only have volumes but does not have any independent mute switch
especially the internal working format is float
0.0 mean mute 1.0 mean 0dB
While most sound cards volume control's min volume are not -inf dB but mute switch is equivalent to -inf dB
for 16bit audio sound card
the range of volume from -inf dB to -96dB is not controlled by hardware
@tanuksaid:Come on Raymond, this has nothing to do with hardware or internal volume representations. PulseAudio has separate mute and volume controls, both work regardless of what the hardware supports, and the volume can be changed regardless of the mute state, so it's purely a pavucontrol bug or feature that it prevents the user from modifying the volume while the device or stream is muted.
This has absolutely zero to do with hardware. It is a software thing. The indicator applet that ships with Linux Mint XCE 14.04 manages to adjust the volume while it is muted just fine.
One of the main purposes of the mute button is to lower an extremely high volume. For all other use cases, the functionality can always be replicated with the volume sliders only. It makes no sense that the mute button would be insufficient for the only thing it is really needed for.
if requested volume is -inf dB, it can achieved by using hardware mute switch or software volume mute but change in software need to rewind and may be deferred when the sink is not playing any stream
https://bugs.freedesktop.org/show_bug.cgi?id=46236#c5
( 20.557| 0.094) D: [pulseaudio] protocol-native.c: Client pavucontrol changes volume of sink alsa_output.usb-045e_Microsoft_LifeChat_LX-3000-00-LX3000.analog-stereo. ( 20.557| 0.000) D: [alsa-sink] alsa-sink.c: Requested volume: 0: 0% 1: 0% ( 20.557| 0.000) D: [alsa-sink] alsa-sink.c: in dB: 0: -inf dB 1: -inf dB ( 20.557| 0.000) D: [alsa-sink] alsa-sink.c: Got hardware volume: 0: 34% 1: 34% ( 20.557| 0.000) D: [alsa-sink] alsa-sink.c: in dB: 0: -28.31 dB 1: -28.31 dB ( 20.557| 0.000) D: [alsa-sink] alsa-sink.c: Calculated software volume: 0: 0% 1: 0% (accurate-enough=no) ( 20.557| 0.000) D: [alsa-sink] alsa-sink.c: in dB: 0: -inf dB 1: -inf dB ( 20.557| 0.000) D: [alsa-sink] sink.c: Volume going down to 0 at 519702599072 ( 20.557| 0.000) D: [alsa-sink] alsa-sink.c: Requested to rewind 352800 bytes. ( 20.557| 0.000) D: [alsa-sink] alsa-sink.c: Limited to 3272 bytes.
it can be easily reproduced using virtual box (emulated ac97) and ubuntu 13.10
open a terminal with alsamixer -c0
in sound preference by pressing mute icon(volume slider change to zero)
Master playback volume and PCM playback volume change to minimum but Master playback switch and PCM playback switch are still unmuted
