An eventful evening in the wilds of Suffolk. Sound check - guitarist sounds fine until he picks up his strat, it starts feeding back and making unpleasant noises. I plug in my bass, and the bass amp starts broadcasting the background noise, and then feeds back too. WTF? After a bit of headscratching - inspiration - there must be an inductive loop somewhere, causing the single coils in my bass and the strat to behave like hearing aids!
Sure enough, I found the culprit and turned it off, and normality was restored. Thank you basschatters, I'm sure my deductive powers were a result of a half-remembered conversation on this forum.
Gig was great - journey home was interesting in the snow. Fire up the Quattro, Polly!!