Ensoniq Mirage DMS-1 Rack. When any system disk is loaded the drive clicks around 10 times and then stops. The screen is either blank or two lines at the top. The synth is frozen - won’t respond to any key presses. A Gotek floppy emulator also freezes.
Funny thing - the formatting disk “FMT V2” works fine. It boots and all the formatting key functions work. A system disk created from this also has the problem described above.
Power supply voltages are fine. I’ve lifted all the socketed chips and pressed them back in. My only guess would be a corrupted 2764 EPROM (labeled 3-0 2206). Does anyone have one of these ?