Expression input doesn't seem to work

I got this used for fairly cheap so I’m not too worried but I just wanted to be sure. I understood that there was some change of names used for the controllers used in Faust, and PD wants “Exp” rather than “E”. My Faust patches don’t seem to respond to anything on E.

e.g.

import(“stdfaust.lib”);
level = hslider("[5]Level[style:knob][OWL:PARAMETER_E]", 0.1, 0, 1, 0.01) : si.smoo;
//========================
process = hgroup(“Level-E”, _,_ <: (_ * level ), (_ * level ) : _,_);

I also tried the “mrFourStep001” patch and it works other than the expression input does nothing leading me to believe perhaps it is fried.

Any experience with this sort of thing? Are they likely to get fried under normal conditions? If it’s possibly fixable with a soldering iron I might have a go at it. I do have a scope and can probably trace the signal to the chip if I get inspired. But I don’t want to waste time on it if it’s hopeless.

I just looked at the schematic. The input essentially goes through a jack, couple resistors with some clamping diodes for protection, across a connector to the daughterboard. I suppose something could be wrong there.

DL