I have a Metaxas Solitaire amplifier that was modified after market. One channel is now bad. I've taken it to three different repair places and none of them have been able to trouble shoot the issue because the amplifier does not match the factory schematic. I'm hoping someone knows who might have performed this type of mods. I'm guessing they would have to be pretty knowledgeable in audio amplifier design to make the mods that they did.