Hey there, i am replying to myself now 
After using ssh to edit the config.txt file and enabling hdmi_Safe=1
I can get into ES. The problem now is, that the resolution and overscan is completely messed up.
How do i change the value of safe mode?
I feel, i am so close to it.
Does anybody know, what the changes between 7 and 7.1.1 are and why normal hdmi mode is not working anymore ?
greeting Thomas
Hey there and merry christmas to everybody.
This is my first post on this forum.
Yesterday i got an update on my Recalbox RPI 4 400.
I was running Recalbox 7 just fine. After the update my TV does show the splashscreen and just goes black after this.
A few seconds later a floaty message from my TV pops up saying that it is an unsupported format.
(Sound Output is working fine, so i guess i am plugged in to the correct hdmi port)
(I am running a LG C9 OLED TV)
It does run just fine on my Samsung TV in the bedroom.
Does anybody have any ideas on how to solve this?
I already did a fresh install after thinking there was a problem while updating.
I am quite new to this topic so i am hoping for some help.
Thx to anyone reading this and helping me in advance.
Greetings Thomas