Diodes usually fail open circuit, unless the heat is so bad that the entire junction completely melts. The only way that could happen is if the AC supply surged tremendously. But then again, if that happened, you would have noticed other stuff breaking connected to the AC.
Was there anything on top of the amplifier which could have fell in (even a strand of hair) and shorted something ?
It could simply be a bad capacitor, from the factory. Although very rare, these may still happen.
Was there anything on top of the amplifier which could have fell in (even a strand of hair) and shorted something ?
It could simply be a bad capacitor, from the factory. Although very rare, these may still happen.