My kid has a MIM Strat with a noisy switch. When switched 1-5 position, positions 2 and 4 hum almost unbearably. He acquired this second hand and apparently the original owner had replaced the pick quard, my son having now replaced it. Is it possible either the original owner re-wired it and messed up something or maybe when my kid re-installed the pick guard that he didn't tuck it back together properly? Or-merely a symptom of he MIM's?

Thanks.
JB

Welcome.

Something's definitely wrong. Ironically, positions 2 and 4 should be the quietest positions. I'd lean towards the prior owner having messed something up more so than your son being at fault for replacing a pick guard on an already wired guitar. It is interesting though, that position #3 doesn't have this problem too. If you could post pictures of the wiring, this would help immeasurably.

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