@ tormedhammaren
if i've understood well, you can see all those activity thanks to the GFX card , , right? if you are be able to see a program loading!
So it is normal that when there is in use a GFX card, you have a black screen on the Amiga RGB output.
Let me know if i've understood :-)
Ciao
PS-check if in the DEVS:Monitor, there is a driver Spectrum related (remove it for testings)