[sdiy] Oberheim Matrix 6 intermittent problem

[S. P. W.]

Hello,

I recently bought a Matrix 6 (with keys)  and (surprise) it has an
issue or two. I absolutely love it so am going to fix it come hell or
high water.

When playing ocasionally all sound output will stop. When that happens
I think the menu stops responding to the keypad. A power cycle will
always fix it right up. This happens maybe once or twice a week, not
every day or every time I play it.

Not a big deal in my basement, but could be a problem at practice or
especially on stage.

I have done the master menu > calibrate function. I am assuming the
calibrate on power up does the same thing. Should I try calibrating at
every power up?

I am good with electronics, and read today that reseating all chips is
a good idea, so will do that very carefully due to static damage being
possible.

At first blush, this problem looks like some sort of voltage collapse
that "shitshot's" the CPU clock. My first guess is to replace all
capacitors with new high quality items, as caps have a finite lifespan
that is very near to the age of this synth. (15 years is a rule of
thumb. These are close to 20)

If someone knows a better place to look, or has run into this before
and knows the answer, I would love to hear it.

take care,

Steve

P.S. Hi all, I just finished rebuilding my Moog opus 3 from a pile of
parts, and bypassed the missing chorus with a jumper by going around
the squelch circuit. I have the skills to fix the M6, but a pointer in
the right direction would be a great help.