Marshall Dynamic Bass System 7400

The problem with this amp is occasionally no sound and pops out of the speakers, the front inputs are loose and the outputs / inputs on the back don't work. We soldered some loose contacts, replaced two input jacks and also replaced all mono inputs and outputs on the back. Replaced the tube socket and tube 12AX7. The outputs / inputs on the back no longer function because someone made connections that are not original. We made it all back original. Ready to rock!