I have an AX-80 which I am restoring. It started out with a broken key, loose pitch bend wheel and several of the membrane buttons which I repaired. I also replaced the worn out power cable which had issues with a new grounded power cable. During this repair several of the solder joints on the power board and other places broke since the unit is so old. I repaired all of them including having to use a few jumpers since the traces separated due to the age of the instrument. The issue I’m having now is every seventh note will not play after the first cycle. In other words, I can sequentially play all notes on one pass. The second time I play the same notes, the seventh note will not play all the way up the keyboard. I have tried swapping out the voice chips to see if this makes a difference but it doesn’t, so I know there are no issues with the voice chips. I also cleaned all of the sockets with deoxit and re-flowed all solder joints with an SMD heat gun on the voice and analog board but the issue persists. Has anyone on this forum seen this issue? I have the schematics but wanted to check if anyone had any suggestions before I start a deep dive with troubleshooting the issue.
Thank you in advance for any suggestions!