Electrical hissing?

[rwb]

i just got a beautiful jet-glo 4003 bass. i mean this bass is just plain gorgeous. i have one problem. i notice that if i lightly touch the strings to the frets, i'll get a small crackle. it gets worse if i run my hand up and down the strings. it seems like a grounding issue. right? i took it into a trusted music shop and they said it's not a grounding issue. they mentioned humidity may be playing a role in the crackling. does this sound like an odd reason for my problem. has anyone had this issue before. thanks
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