I use a Sinclair ZX Spectrum Issue 2 with a DivMMC EnJOY! Pro One and the boot process shows no error and I'm even able to enter the file browser but if I choose any game/demo/program I get always garbage:
YouTube Link: https://www.youtube.com/watch?v=9bGBzDCBbKk
Here my CPU (NEC D780C-1) with modification: https://i.stack.imgur.com/syNPq.jpg
Any idea what's wrong here?