Since the latest update and the ones before we are facing audio problems on some movies and tv series…
We are using an RPi2 that is hooked up thru HDMI to a Samsung HT-D6750W, and on most movies the sound is perfect, but on some movies the sound is fuzzy and comes and goes. Sometime we can hear it perfect, and switch to only be music and when people are speaking we can´t hear it at all.
Nevermind if it´s 5.1 or 7.1 audio track in the movie or tv serie! 
Any tip?
Perhaps comparing the codecs used for the movies that have ‘fuzzy sound’ to the ones that sound OK might shed some light on whether this might be codec related. MediaInfo is a cross-platform tool that can provide that info.
If that doesn’t provide any insight, you’ll probably have to provide logs 
Try playing a film. Press “select” to bring up the on screen display, navigate to the audio icon on the right hand side. Increase the Volume Amplification to about 10. This resolves the issue for me. At the bottom of that menu select “save setting for all” or similar, going by memory here.
Lets see here…
On one of the files we have problems, it´s listed as follow:
1 video steam: AVC
1 audio stream: AC-3
6 channel AC-3
Your issue has nothing to do with codecs…
Will try that and reply back with the results…
In system/audio settings make sure number of channels is set to “2.0”.
It is likely your TV doesn’t support mulit-channel PCM so setting that to e.g. “5.1” will just mean you only hear the surround track and not the dialogue.
Our home theater is a 5.1 and supports virtual 7.1! So yes, we can use 5.1 channels…
Update: Nope, turn up 10db on Volume amplification didn´t work to solve the problems we are facing after the latest updates. 
http://kodi.wiki/view/Raspberry_Pi_FAQ#How_about_multichannel_audio_support.3F
Multichannel PCM audio is supported over HDMI. Note: not all receivers support this and toslink/optical will not.
If your recevier does not support multichannel PCM, then leave this at 2.0. You can still get multichannel audio through passthrough.
Can you confirm the connections? Is it:
Pi <–HDMI–> HT-D6750W <–HDMI–> TV
(rather than connecting the Pi to TV and using ARC to the receiver).
I assume you are not using the audio output of the TV, but always using the HT-D6750W?
Do you have passthrough enabled in system/audio settings?
Hi all again!
Ok, so a little more tests from my side now:
Changed from 5.1 to 2.0, nope, the sound did not get better!
Changed the volume amp when using 2.0 to 10dB, the sound went hearable but not good!
I will record a couple of small videos to show the problem later on. And yes, the connection is Pi <–HDMI–> HT-D6750W <–HDMI–> TV.
The problem is that this is only happening on some shows and movies, and not all of them!
Best
Pontus
