2- ADA MP2 pre amps for parts not working but,  it might be easy fixes for someone with electronics skills,  one of them the battery 
connection to the board broke off and the other had the signal cutting out,   I disconnected the transformer on the opened unit to make sure my working unit had a good transformer and it ended up being another issue I fixed so it's just disconnected,  the Mp-2 units sound almost the same as the Mp-1  but you have to flat line the EQ and use the right distortion setting.