At Thu, 13 Mar 2014 21:20:46 +0800, Raymond Yau wrote:
sam chan wrote: i'm having a problem with sound volume being too low. i **think** it's due to the levels of my channel map being too low.....
The channel map specifies which channel goes to which physical output.
my alsa-info... http://www.alsa-project.org/db/?f=3ba6278df3c6c4abe5196ad37f8015de7223ca8e
Simple mixer control 'Master',0 Mono: Playback 37 [59%] [-39.00dB] [on]
That is pretty low.
Simple mixer control 'Loopback Mixing',0 Item0: 'Enabled'
Why is this enabled?
seem driver bug
Not really.
- Should the volume control and playback switch of line out be named
as Front instead of PCM ?
Depends. For multi-channel setup, we take "Front", but in other cases, it may become "PCM". It's suboptimal, indeed, and we need a better naming rule for the shared volume control.
Node 0x05 [Pin Complex] wcaps 0x400185: Stereo Amp-Out Control: name="PCM Playback Volume", index=0, device=0 ControlAmp: chs=3, dir=Out, idx=0, ofs=0 Control: name="PCM Playback Switch", index=0, device=0 ControlAmp: chs=3, dir=Out, idx=0, ofs=0 Control: name="Line Out Jack", index=0, device=0 Amp-Out caps: ofs=0x3d, nsteps=0x3f, stepsize=0x05, mute=1 Amp-Out vals: [0x23 0x23] Pincap 0x00000017: OUT Detect Trigger ImpSense Pin Default 0x01014010: [Jack] Line Out at Ext Rear Conn = 1/8, Color = Green DefAssociation = 0x1, Sequence = 0x0
- dB max of virtual master playback volume is different from the
slave when slave dbmax of slaves > 0
It's the designed behavior. The Master volume is an offset applied to the slave value, thus it's always up to 0dB. The lowest value is somewhat bogus, but it's anyway cut off under 0.
Takashi
control.1 { iface MIXER name 'PCM Playback Volume' value.0 61 value.1 61 comment { access 'read write' type INTEGER count 2 range '0 - 63' dbmin -9150 dbmax 300 dbvalue.0 0 dbvalue.1 0 } } control.3 { iface MIXER name 'Headphone Playback Volume' value.0 61 value.1 61 comment { access 'read write' type INTEGER count 2 range '0 - 63' dbmin -9150 dbmax 300 dbvalue.0 0 dbvalue.1 0 } } control.5 { iface MIXER name 'Speaker Playback Volume' value 61 comment { access 'read write' type INTEGER count 1 range '0 - 63' dbmin -9150 dbmax 300 dbvalue.0 0 } } control.17 { iface MIXER name 'Master Playback Volume' value 37 comment { access 'read write' type INTEGER count 1 range '0 - 63' dbmin -9450 dbmax 0 dbvalue.0 -3900 } }