Very late response I know but I've just spotted this thread.
I used to have a (cheap) wireless from Tesco's which my lights interfered with.
So I recently bought the BC1606L wired + cad, I've had a similar problem with the front sensor moving slowly every time I do a kerb jump etc.. So what I did was took it off and removed the bit of foam padding off the back and put one of those double sided sticky pads on the back (a.k.a. motor factors) and then re banded it to my front fork. It's not moved since. BTW, I didn't get the "thick" sticky pads that you would use for an interior mirror, these are quite thin, about 1mm, actually bought them from A1 Motor stores.