Vintage Synth Repair

I have a Kurzweil SP88x that the display has started blinking. If I hit a key when the display is off it will not play but it will start to sound as soon as the display comes back on while still holding down the key. These cycles are short, so when I play the sound come and goes with the cycle on the display.

I switched out the wall wart but that did not remedy the problem. I am a player not a tech but, if possible, I would like to fix this myself. I have had the case open and removed the keyboard before so if it is just a matter of replcing a component I think I can do that. I would not attempt to take a soldering iron to a PC board.

Has anyone here seen this before?

Thanks,
Dan