Severe static on power up

I know that I have seen this problem in thus forun before but I cannot find it now.
Sometimes when I power the unit up I get severe static from all speakers. I have to power down and then back on several times before the problem goes away. I now leave the unit on all of the time and just turn the input selector to a dead input.
This past week the unit is putting spasmodic noise through the center and both front speakres. It is a crackling noise and no matter what volume level I am playing the unit at the noise still comes across very loudly.
Can you suggest a fix and please direct me to the thread where I have seen other problems with static noise.
Thank you