I am having problems with some arcade cores, but I checked the checksums posted here and they are correct.
Bombjack and pheonix work
burger time, donkey kong, frogger, galaga, galaxian,moon crester, mspack man, pack man and time pilot all give me a blank screen, the leds go off and none of the buttons on my IO board do anything.
This is the same on HDMI and VGA.
Can anyone offer things I should check ?