Valve stage coupling capacitor leakage?

[b1o2r3i4s5]

I've constructed a simple 2-stage valve preamp (voltage gain and cathode follower).

Each of the stage works fine independently, but once i put the stages together with a capacitor the cathode follower's bias voltage changes and puts it in cut-off state.

Im suspecting that its caused by the coupling capacitor's leakage but i can't be sure, I'm currently using a 250V Metalized P.E. cap.

If it is caused by the leakage, then how do i solve it, if not then what other causes could there be?

 

[SY]

A schematic would help. If you have photos, that would also be nice (it COULD be as simple as a wiring error).

 

[DF96]

Coupling capacitor leakage almost always turns the next valve on too hard, not off. My guess is that you have a circuit or wiring fault. A diagram would help.