K6 problem

["Max" oatcruncher]

Having three ME66/K6 mics, I recently decided to sell one. This is where Mu=
rphy's Law kicked in. A week or so later I come to do some recording using =
the two that are left, and guess what; a problem! After much swapping I boi=
led it down to a problem with one of the K6's. I'm getting a background cra=
ckle.  I tried all the usual basic things like checking nothing was obvious=
ly loose, and that contacts were clean. All of this to no avail. I rang Sen=
nheiser and they're quoting something like =A360/$100 an hour to repair it.=
 Has anyone on the group had a similar experience by any chance, and if so,=
 what's the likely cause please? Any explanations welcome!
Max
p.s. this was using phantom power.