What the point in C5, C6, R3, R4? They do nothing useful in this circuit. Series resistors negate any effect 100n capacitors might give. Not to say C11, C12, C13, C14 will have barely any effect as well, if any at all. Wires between PSU and AMP will negate any effect of decoupling capacitors located in PSU. Considering capacitors used, looks like implementation of what people often call audiophoolery.