replacing a Vtl 5c4/2 for a Vtl5c3/2

[capmando]

Anyone have experience with replacing a Vtl 5c4/2 for a Vtl5c3/2, any modifications needed?
Having an issue with a Fender super 60 channel switching, input goes dead after switching over to either
Channel. Pluging a jack from line out to Amp in seems to help sometimes.

Any thoughts would be appreiated.
I hope everyone is dry after the storms and did'nt lose to much, whew!
Capmando

[PRR]

I don't know. In a switching scheme, probably either will work.

[capmando]

Much obliged for the reply.