Amplifier Issues....

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The amplifiers are Rod Elliott's P3A
The preamp is Rod Elliott's P97

100W x 2 stereo amplifier, the power supply is a 300VA toroidal transformer with a 35A bridge rectifier and 2 15000uf, the preamp has Rod Elliott's P05 as its power supply and a small standard transformer for it (not toroidal)

Before I put it in the aluminum chassis it was working perfectly, low noise, high stability. After i put it in the chassis i get noise and the transistors seem to try to go into a thermal runaway when have an input connected but nothing playing and raise the volume high. i hook my ipod directly to the input of the amplifier, not through the preamp, and it works perfectly
I've checked for shorts there seems to be none

i notice i get more hum when i hook the house's earth to the chassis, and most of the noise goes away when i don't hook the house's earth to the chassis and hook just the amplifier's ground to the chassis

:mad::mad::mad::mad:
 
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