Whats up with this Valvetronix?

[matt99camero]

I picked up my other head yesterday. This one is in better shape but has some weird things going on. The guy has a short cable(George L's) running from the effects loop send into the effects loop return. I didn't really notice it until I got home and I unplugegd it, then the sound started cutting in and out. When I plugged it back in it was fine. I've never really messed with effects loops so is this thing messed up or what? My other head is just fine without anything plugged into the effects loop.

Also, when a guitar is plugged into the high input it sounds fine. But when plugged into the low input it makes this weird noise. He gave me a little thing thats a 1/4 plug with a resistor in it. When this is plugged into the high input it sounds ok. So whats up with that?

Here are some pics so you know what I'm talking about(sorry for the crappy pics)
the effects loop

the guitar plugged in and the resistor

the resistor thingie

 

[Gr8Scott]

Re: Whats up with this Valvetronix?

On the effects loop, I'll bet the switch built into the loop return jack is weakened or dirty. Clean both jacks thoroughly with contact cleaner and see about that return jack. Maybe use a dental pick (with the amp unplugged) and reach in the jack with it and spring it back out a bit so it disengages properly.

On the inputs, the high sensitivity side is usually unusable to me as it makes the amp squeal and make horribly nasty high pitched noises because my guitars overload the amp. Even my strat pups overload the high input. The low input works well with everything I have. Seems like this dude modded the amp to me.