Need advice on ARC SS Amp stored for long time

I'm the lucky guy (or not) who found and bought a brand new Audio Research DS-450 solid state amplifier in the sealed box! This amp has been in storage for at least 12 years, maybe longer! I have paid US$ 4.000 for it with no warranty from the vendor.

I haven't turned on the amp yet!

When I opened the box and took off the top cover I found some signs of mold as you can see in these pictures:

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But what is making me worried are 4 capacitors. I don't know if it's moisture or if it's a possible leak.

See the pictures:

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There are no signs of leaks at the bottom near the PCB, only at the top of them.

What do you think of these capacitors? Mold or Leaking?

I'm thinking of using a Variac transformer to slowly increase the voltage to try and slowly reform these capacitors and see what happens. This amplifier uses a linear power supply, but I don't know if its protection circuits will allow that.

What should I do? I would really appreciate if you guys could guide me.

Thanks a lot!
 
Looks like glue or sealant spatter.
The gradual on with a variac plan is a good one. Even undamaged capacitors go past a shelf life where the aluminum oxide deteriorates and needs to be reformed. Usually 18 months to 3 years after manufacture.
 
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