I got got a nice used Fender Stage 112 SE solid state amp in a trade. The problem is that there's a constant humming noise. I've tried playing other guitars through it but the same problem. I've even tried moving it to other parts of the house. Does anyone know what I can do about it or is it normal for this amp? Thanks!
it is not normal

take it to a different place altogether

are you using 3 prong outlets or 2 prong?

do you have lots of other electronics around?

is your guitar grounded properly?

are you using any effect pedals?

may be a crossed wire somewhere?

do you have any friends that are EE's?