The power supply is likely to be dual power supply,supplying both positive and negative volts to the amplifier circuit.In that case it must provide positive and negative voltages to the circuit.Then the polarisation is wrong.I think the amplifier uses some operational amplifiers which may require double voltages.point 1 in your supply must be positive.Point 3 is negative.point 2 is ground.Hence the positive of the cap should be connected to pin 1.Its negative must be connected to point 2.Similarly,the other cap's negative must be connected to the point 3 since it is a negative supply line.This cap's positive must be connected to point 2. I hope you understand the principle