Millenium 2 mis-behaving

[brett]

Hi.  I have a M2 circuit that is switching the LED off when the effect is bypassed, but the LED comes back on after about 30 seconds.  I've built about 20 pedals with M2s in them and never struck this before (or any other problem).  The "change" pad is connected to the DPDT as usual, and there's an output pot in the effect to provide grounding for the "change" pad when the effect is bypassed.

At first I thought that the 1N4148 (=1N914) is leaking so much that the 50k (or thereabouts) of resistance to ground through the pot isn't enough to pull the gate of the mosfet down.  But if that's the cause, why would the LED turn off, then back on? Also, touching the "change" pad or gate with my multimeter turns the LED off (so it appears that the 1Meg resistance of the meter is enough to pull the gate low).

I'm confused. This must be simple.  :oops:  
Any suggestions?