[mythtv-users] Confused 5.1 Sound Mapping?

[Jim]

On 08/03/2015 11:28 AM, Jim wrote:
>
>
> On 08/03/2015 10:35 AM, Tim Draper wrote:
>>
>> ---- On Mon, 03 Aug 2015 14:37:27 +0100 Jim  wrote ----
>>> I am experiencing an odd mapping of the 5.1 sound channels. The
>>> materials I've found on ALSA and Pulse have not led me to a remedy. 
>>> I've
>>> tested all available configuration options in the Audio Setup, all with
>>> the same result.
>>>
>>> The sound is not simply a front-back misalignment. When performing the
>>> 5.1 speaker test built into Mythtv, or using speaker-test I find the
>>> following:
>>>
>>> front left out of front right
>>> front right out of rear left
>>> rear left out of rear right
>>> rear right out of front center
>>> front center out of LFE
>>> LFE out of front left
>>>
>>> Has anyone else experienced this and have any idea of how to fix it?
>>>
>> i'm going to start with the basics:
>> - how are to connecting the FE to your speakers; AVR, amp, or direct 
>> speakers?
>> - does 5.1 work correctly when you use another device via 
>> same/different connections?
>> - i use pulseaudio for my setup and do get channel mis-configuring on 
>> first install before i've configured it. Have you ran 'pavucontrol' 
>> on the desktop and configured your output type correctly. iirc it's 
>> on the last/2nd-to-last tab where you get various options like 
>> analogue stereo, digital stereo, digital surround, spdif etc as the 
>> output method.
>>
>>
>> my last install refused to work correctly. a fresh install & 
>> configure pavucontrol fixed it.
>>
> The computer is connected via HDMI to a Yamaha RX-V575 AV Receiver. 
> The receiver is directly driving all 5.1 speakers, and is connected 
> via HDMI to the TV. The TV speakers are off.
>
> A Blu-ray player is also connected via HDMI to the receiver. All 5.1 
> sound is normal when playing DVDs and Blu-ray discs via this player.
>
> I have run pavucontrol, selecting via the Configure tab the Digital 
> Surround 5.1. (HDMI) Output.  The Output Devices tab shows the 
> expected information.
>
> I am glad to learn others have discovered and conquered this problem. 
> I am sad to hear that it may take a new install. Is there no way to 
> correct the mapping without a complete new install?
>
>
I may have found a solution to the wrongly mapped 5.1 surround sound 
problem. There is a module, called module-remap-sink, available in the 
pulse audio module suite that supports remapping of all the speakers. 
I've not tested with all possible configurations but at least one 
configuration is working properly and now the sound is coming from the 
correct speakers. There may be more to address, but at least the wife is 
happy for now!