Share 'Strat pickup volume problem -- advice please'

I recently switched out a 250k volume pot on a strat. The problem is that the customer has voiced a complaint that since he got the guitar back he has noticed that he gets very little volume from both the low E and D strings on the neck and middle pickups ONLY. The bridge pickup is a JB jr. and that picks up the signal and sounds terrific through an amp. Acoustically the guitar sounds just fine w…