Yamaha P7000S - several failures lately.

[Pilsener]

I have hardly ever had any of these amps in my workshop for repair earlier. They just don't seem to fail.
But now there have been 2 failures during the last month.

They have the same symptom:
The PSU's switching transistors and the ICs are blown to pieces. Litterally.
The amp's output stage also have some failed transistors, but I cannot tell if this is caused by the PSU or vice versa.

Have any of you experienced an increase in failures of the P7000S lately ?
Or do you know any reason why this happens ?
I have a couple of these myself, and I would like to take precautions if possible.

[Jazz P Bass]

Kind of a chicken/ egg debate.
Did the outputs go & take out the SMPS or vice versa.
When the SMPS goes there is really nothing to stop the destruction
The mains filter cap of SMPS's takes a beating.
As to preventive maintenance that is a good one to replace.
Also resoldering of the main components goes a long way to keeping an amp running.
The fact that you have two in for repair is either an age issue or a coinsidence.