It looks like the Blue and Yellow wires are reversed, as long as the wires are connected correct on the PCB.
Check the colour of the 2 wires that are closest to the headphone jack, directly behind the jack on the PCB.
They should be the positive wires, the 2 wires closer to the back of the amp are the negative wires.
Cheers
Mick
Check the colour of the 2 wires that are closest to the headphone jack, directly behind the jack on the PCB.
They should be the positive wires, the 2 wires closer to the back of the amp are the negative wires.
Cheers
Mick