Hypex SMPS issues

Hi

I've a couple of SMPS 1200/A700 powering two NC500s, effectively twin mono amps.

But the entire amp gave up the ghost recently. Hypex advised that the likely problem resided with a couple of the caps. odd though that they both failed on the same day.

to avoid looking completely stupid can anyone advise a test I can carry out to understand where the problem is?

cheers