Pickup 'clack' but strings aren't even close

[Stingray5]

Hoping someone can shed a little light on this problem.

Jazz bass - suddenly when slapping on the E string, I'm getting what sounds exactly like that magnetic clacking sound as if the string came into contact with the pole pieces. But there is definitely no contact. I even lowered the pickup all the way and it still happens.

Definitely wasn't happening before, nothing changed. Just suddenly started.

I THINK it's only the neck pup, but here's the kicker - I took a jazz pickup and all electronics from another jazz bass, hooked up just the replacement pup to the different pots, and it's STILL happening!

I read somewhere else that maybe it's a grounding issue, but there is a ground wire grounded under the bridge to the tone pot. Also there are no other signs of ground problems - no hissing or anything.

The bass is fine otherwise - it only happens with anything over a moderate force slap on the e string.

Any ideas on this odd problem?

[aquateen]

maybe you're hearing the string hitting the upper frets?

[tramp]

Or your finger hitting the string

[gimmeagig]

I've had that problem on a Jazz bass and I had the pickup dipped in parafin.That helped a little, but the bass was still touchy.Try taking some relief out of the neck and lower the action.You might even have to shim the neck.Then look at your attack.Don't hit the strings too hard, just enough to get the string to hit the fretboard.Then lower the front pickup until you can get the clacking to go away.

[debassr]

Well, first thing is to find out if the string is indeed hitting anything.

I would check the clearance between the frets.
Also check to see if a fret wire hasn't come loose.
Also check your nut for signs of excessive wear, cracking.
And check the bridge and make sure the intonation screws are tight and in good order.

Last, try changing out the string.

[Stingray5]

thanks all for the suggestions so far. I checked everything and all is good..

New development though:

I found that just tapping on the neck pickup produces the loud pop/clack! Not on the poles - just the black plastic part - and it's exceptionally loud.

So this seems to be what the problem is.

But now, what do I do?

Is it some type of ground problem? Remember I've ruled out the pickup and the pot themselves because it was still happening when I swapped them out for testing.. very confused about that!