I already managed to fix the drive that wouldn't read.
The remaining issue is a part on the back of the motherboard that's been damaged.
Because of this, in the RGB, i only get Blue, a bit of red ..somehow, as the tint is more purple than blue.
I looked up some things, found some help, but now....to dive in and repair it/replace it...i have no idea what part i should be looking for.
Maybe i could wire the lost connections to R and B (pun intended) but the ZD401 looks damaged.
I would be beyond happy if people here, who know these things way better than me, could help me fix this dreamycast.
Another bit of info :
it's for sure something, probably this thing, on the board and not cables or my TV.
My other dreamcast has no issues going through the same cables (dreamcast AV to Scart) and TV (Beovision MX4200).
Here are a few pictures
