No input front or rear MP-1

[Mxzx]

Yes I have input signal on 3 of the 8 terminals on U4.

Thanks

[Mxzx]

Well the MP1 is finally fixed, many thanks to MarshallJMP!!!

Turns out it was a socket that was put in for U4 by previous owner.  Used a little too much solder and bridged 2 terminals under socket.

[MarshallJMP]

Well actually you found it,so all the credits go to you !!