Gerry R

After getting a power outatage, amp started generating very loud noise on switch on. Tried disconnecting, unplugging etc.. and still just getting that horrible noise, almost like an old alarm clock, just very amplified. I realize it's an old amp. Has it finally ran it's lifespan? or is there any way to fix this? There is no screws but rivits holding it together, and didnt want to open it up.