[Cube 3rd + Kodi 21] – Audio delay (fix applied)

I finally came around to set up my new Cube.
First I installed v20, but then I saw the Audio problems, so I upgraded to v21.
I applied the advancedsettings fix and it looked as if it´s works, but it does not.

I cannot say when it happens, once it works without problems at the beginning and then after some minutes it desyncs. Sometimes after 5mins, then after 40mins.
Sometimes a Video restart does fix the problem, often it somehow does not.

Debug Log

FireTV Settings is “Best available”.

Any ideas?