Peavey GPS 900 pwr amp

[e_c_mccollum]

Got an interesting problem. Amp works with unbalanced inputs but not on balanced inputs. Polarity switch is set correctly.

Sometimes, it will work with balanced inputs but only on channel B. Being used as a high amp in a three way system. Does'nt matter if 1/4 or xlr is used. Wondering if cheap combo jacks on the inputs or bad.

[Enzo]

Get the schematic from PV and see if there are any circuit considerations you have overlooked.

Get some clip wires on the inputs and see if you can send a balanced signal in without using the jacks.