the power supply comes with overvoltage protection, why it is still havin AC noise?
while Hero999 already indicated, i would like to add that the electrolytic capacitors have a life time
and they deteriorate. At times, we see capacitors with a bulge on their top, a definite indication of its failure. I know of service Engineers in India, prefer to change all electrolytic capacitors as a batch, with same type and quality. It extends the life of the power supply, provided, of course, the Main and Aux transformers did not deteriorate.