Oberheim 6R Screen Issue

Hey there, first post and happy to be here.

I’m having a pretty odd issue with the screen of my 6R. It seems to blank out at a random time either if I’m using the front panel or sending MIDI to it. Sometimes when I boot the synth back up the characters are all scrambled. If I reboot the synth and calibrate (hold STORE button on startup) the screen comes back to normal to only blank out again some time later.

I’m running Bob Grieb’s v2.15 OS but I was having the same issue with the original v2.13 OS. The PSU voltages checked out OK, put a new battery in and also changed the fuse on the screen board. Everything else with the synth is working perfectly it’s just that the screen blanks out at random!

Thanks for your help!
Turbo