Vintage Synth Repair

Thanks for letting me join the group, I'm a vintage synth fan from way back.   My beloved OB-X has started acting up lately and I'm going to be doing repairs on it for the first time since I bought it 15 years ago.

The symptoms are that I turn it on and some button lights come on and the buttons respond, some don't.  All patches are gone, some patch slots make sounds that are very sick sounding, others are empty.  The Autotune selector on the front panel lights on and off, but I see no LEDs lighting up showing that Autotune is doing it's tuning sequence on the sound cards.   I've replaced the 3V Lithium battery, but nothing changed.

I've already found some great reference stuff on other sites and now realize that I'm probably in for a wild ride to fix things.  But I would greatly appreciate any help from anyone who has experience with OB-X repair.

Thanks!
Rod