I think there's a ghost in my house.

Sitting in the dark, I occasionally witness a compact flourescent bulb
light up very faintly, for no more than a second. Two lights (on two
different circuits) do this.
The first is in a stairwell and switched by two three ways and one
four way.
The second is switched by two three ways.

I've had two electricians look at it and find no apparent problems
with the wiring in the switch boxes. I should state for the record
though that I wired the switches for the first light, and I'm not an
electrician. One of the fixtures had the black and white wires
reversed, but correcting this didn't change anything. The switches
for the first fixture are all brand new. Those for the other are 50
years old. The house is wired with BX cable, except for renovated
areas, including one of the lights. Both lights are grounded just
fine.

Here's the puzzle: using a meter, the lights register 30V from black
to white when the switches are set to turn the light *off.* Does
anyone have thoughts on what could possibly cause this?

By the way, one electrician noted that when one touches the black to
ground, nothing happens -- no spark, no short, nothing, so maybe the
meter is misleading us, but then the other electrician registered the
same thing on his meter, and remember, the bulb lights up.

Ultimately, I'll probably just have an electrician rewire the whole
damn circuit, but I sure would like to know what's wrong first....


Thanks for any advice