@teufelskrapfen

Hi,

I had the same issue with my system and your post gave me an idea.
In the latsest version of recalbox (6.1), I did this:

go to /etc/init.d enter command: mount -o remount,rw / open file splash03 change line 88 as follows:

omx_opt="--adev both --no-keys --layer=10000 --aspect-mode=fill"
omx_opt="--adev local --no-keys --layer=10000 --aspect-mode=fill"

save

Actually, "adev" must be followed by one these options: hdmi/local/both.

Hope it might help.