mate, I've heard of this before and a mate of mine came up with a solution that worked for him as his was nearly the same as yours....the psu on the unit is the issue here, so perhaps get a new 1 with the same specs its a linear psu thats supplied with it and thats giving too high a voltage on the unit, so get yourself 1 of these
psu which is a switching psu and you'll be fine. you need to have it at 4.5
