Just got my new N2 and get a terrible hum from my Line 6 Spider IV amp. The volume knob on the guitar seems odd, that is, I turn it an 1/8 turn and its goes from silent to loud, the rest of the 7/8th nothing changes! Also when I put the guitar on my lap the hum stops but if I lift and turn it it hums again. I've tried other leads just the same. This doesn't happen with my other guitars. Help - What's the problem???