[606u]

Every time I open System>system>video output, I get the message "Save resolution. Would you like to keep this change"
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With the 2 players I have a drop at the very beginning of the file and can't listen the half first second.

I have the same two problems, except I got the message "Save resolution..." twice: here is a short clip; message also appears when video settings are opened right after a restart (while Pi is restarting TV and receiver are switched on and TV's active input is the receiver).

Update: Initial interval where no sound is heard could possibly be related to the receiver: the time it takes to detect the format of input signal and set-up the appropriate decoder, hence it is audible on 1st track. Pause seems to also appear when audio format is changed, like PCM => DD or between different bitrates and frequencies of PCM. If that is so, there is little that can be done.