[MrNice]

@popcornmix

Clean install in formatted SD card: build: #0224

Personal set-up:
Network Wi-Fi
Service SSH
Apparence > International > UK (24), Timezone
Music > Playback > Visualisation: None
System > Video output: 1680 x 1050
System > Audio output > Number of channels: 5.0
Input device > Peripherals > CEC Device to power on: AVR, Device to power off: AVR, When the TV is switched off: Ignore

I did few reboots along setup without playing
After I tried playing flac 2ch file with default PAPlayer: No sound nether system sound
As usual, I changed the screen resolution: Still no sound with default player
Then I tried OMXplayer and sound is here system sound as well
Then tried again with PAPlayer sound is here as well.

Then I switched off the RPi (no power) and restarted it
Tried to play same flac file, no sound with the 3 players and no system sound.
Changed the screen resolution: As soon I clicked the window "Would you like to change the resolution?" YES, I can hear the system sound then flac file played fine.
Find log here from the second boot.

Hope this will help to find the issue