Sega Mega CD Pro CDX v1.80i problem and solution...
Had another look at my faulty Datel Pro CDX import player cartridge for Mega CD. The thing only worked every once in a blue moon. So I opened it up and replaced all the parts that could cause trouble. Being one capacitor and one mosfet. Also cleaned the pin connector thoroughly. To no avail. Still, I managed to find out what the problem was. Apparently the thing is very sensitive to residual energy. Every time I used the cartridge I have to unplug the power brick with the cartridge still in the console, and move the Mega Drive power switch on and off for a second to release any residual energy. After that I plug it back in, and it works like a charm every time. The more you know...