Humming Noise, Problem?

I have an Accuphase E202 amp, it has all new electrolytic capacitors on every circuit board in the amp, along with 4 new 10000uf 80v power capacitors. The amp makes a humming sound when powered up, but when the relay clicks, it's dead quite, works 100% perfect. Is this something that needs to be taken care of?

How do I fix it? :confused: