Sound distorted on RPi, remuxed MKV?

Recently I’ve remuxed some films - usually within MKV container.
Reason being to remove unnecessary audio or to make the default one different.

I kind of went mad when I played one of them and instead of audio there is a sound of huge fly, hitting the wings against a window.

I can’t say where is the problem. At the weekend I will try to restore an older version of the system - before recent update.
Before I came across this problem I was quite sure I didn’t have this problem before recent update or else within last time, as I have quite a few remuxed films in my collection

Above and Below - MediaInfo from one of the films

ID/String : 2
Format : AC-3
Format/Info : Audio Coding 3
Format_Settings_ModeExtension : CM (complete main)
Format_Settings_Endianness : Big
CodecID : A_AC3
Duration/String : 1h 48mn
BitRate_Mode/String : Constant
BitRate/String : 448 Kbps
Channel(s)/String : 6 channels
ChannelPositions : Front: L C R, Side: L R, LFE
SamplingRate/String : 48.0 KHz
Compression_Mode/String : Lossy
StreamSize/String : 346 MiB (18%)
Default/String : Yes
Forced/String : No

any ideas guys?

It sound a bit strange as you have been using mkvmerge but you still might want to check this thread Kodi 15 - some mkv with mp3 audio -> no audio

Generally I suggest give it a try on a different Kodi Isengard system (e.g. on your notebook) if the issue remains open a thread on the Kodi Forum

I’m already sure it’s not a problem with remuxing. I was going through the list of films I have already watched, and I found several - to have the same distortion.

I won’t do anything at the moment as any restart will damage my qBitt downloads, but if no fix found/released I will recover my last full backup and take it from there…

Other symptoms: cant mute the distortion on OSMC - only ‘tv volume down’ will work; within one MKV/film - one of audio lang may be distorted, the other not.

will update later

recovering system from SD backup and upgrading/updating OSMC/Kodi again, solved the problem