An update for the OP - and everyone else.

Mine has the buzz no matter the pickup setting. Never had it previously. The shop couldn't find an issue with the wiring and are sending it to their guy that does all their bigger electrical works as it seems to be more of a problem within the preamp itself.

Looks like I am sans bass for another week, but hopefully will be good as gold as this one looks to be heading to a new home in exchange for a Trans Burg (dark red) Stingray 5H.