[mythtv] [mythtv-commits] Ticket #8798: DD5.1 does not play correctly when timestretch is enabled.

[BP]

MythTV wrote:
> #8798: DD5.1 does not play correctly when timestretch is enabled.
> -----------------------------------+----------------------------------------
>  Reporter:  jpoet                  |           Owner:  jyavenard  
>      Type:  defect                 |          Status:  closed     
>  Priority:  minor                  |       Milestone:  unknown    
> Component:  MythTV - Audio Output  |         Version:  Unspecified
>  Severity:  medium                 |      Resolution:  invalid    
>  Keywords:  AC3 DD5.1 timestretch  |   Ticket locked:  0          
> -----------------------------------+----------------------------------------
> Changes (by jyavenard):
> 
>   * status:  assigned => closed
>   * resolution:  => invalid
> 
> 
> Comment:
> 
>  That option isn't active by default.
>  It shouldn't even be available for spdif (option is either greyed out, or
>  not displayed at all).
>  This option is only available if the audio device reports supporting more
>  than 2 channels. If it reports more than 2 for the spdif port, it's an
>  ALSA bug
> 
>  I'd be interested to see the log again with -v audio ; it now shows in the
>  log the number of channels supported for each audio device
> 

For me, the option is greyed out, but checked/enabled.  Time stretch has 
been broken for me since the audio changes that introduced that 
configuration.

Thanks to this ticket pointing the right direction, I was able to make 
time strech work again by directly setting MultiChannelPCM to 0 in the 
settings table of the database (also unchecks the greyed out setting for 
LPCM).  All my frontends had MultiChannelPCM set to 1.  As the option is 
greyed out, there was no means I could find through the settings UI to 
disable LPCM.

Without knowing how it got enabled, perhaps the Audio settings page 
should disable LPCM as part of greying out the option?  Having to hack 
the database if it gets enabled for some reason is not the best option. 
  Or at least the "dirty fix" mentioned in comment 6.

I could also see a potential issue if someone changes sound cards for a 
given hostname from one which had support to one that does not thus 
getting them stuck with this setting enabled.