Strange guitar vol / tone behaviour

inewham

If I plug my Strat it into my Kustom Coupe 36 the tone doesn't make any difference and the volume goes from full to zero by 7 or 8

if I put a pedal in between its fine

If I plug into any other amp, vol & tone work as expected, a gradual reduction in vol/treble from10 to 0

Has anyone seen this kind of behaviour before?

I was thinking something might be odd with the impedance of the input, it goes through a 47K series resistor with a  1M to ground straight onto the grid of V1.

Valves are new Tung Sol, less than 6months of occasional bedroom use. Pots are about the same age (CTS 250K)

I wont get chance to get the tools out until Friday...

inewham

Ignore - duff cable (measures 2k)