#12527 NORM 4-softw: XO-4 volume adjust is too coarse

Zarro Boogs per Child bugtracker at laptop.org
Sun Mar 3 20:38:34 EST 2013

#12527: XO-4 volume adjust is too coarse
           Reporter:  wad           |       Owner:                   
               Type:  defect        |      Status:  new              
           Priority:  normal        |   Milestone:  4-software       
          Component:  not assigned  |     Version:  not specified    
         Resolution:                |    Keywords:  XO-4 audio volume
        Next_action:  diagnose      |    Verified:  0                
Deployment_affected:                |   Blockedby:                   
           Blocking:                |  

Comment(by Quozl):

 the key presses are effectively doubled, because amixer processes the two
 channels of the master mixer one by one, applying the 10% adjustment

 along with an error in rounding, this explains the observed result.  there
 is a [http://git.alsa-project.org/?p=alsa-
 utils.git;a=commitdiff;h=da1c24a24c699125aedc8d4f7c97d974b868dacf fix to
 rounding], but the underlying problem remains; of the master mixer control
 having two advertised independent channels that are not implemented

 perhaps ''Master'' should not present both a front left and front right
 channel, instead only presenting a mono channel.

 (because of rounding, the range of control values varies according to
 whether the control is started from fully on or fully off.  on the way
 down the values are 100%, 79%, 59%, 38%, 18%, and 0%.  on the way up the
 values are 0%, 21%, 41%, 62%, 82%, and 100%.  levels below about 30% are
 inaudible in a typical environment.)

Ticket URL: <http://dev.laptop.org/ticket/12527#comment:5>
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