Stuffing box, exhaust hose are not the problem. No water tracks.
Mast is deck stepped. Wiring passes through the deck but that's not where the water is coming from. (vhf cable goes down through the compression post and out the bottom in one of the "boxes" that runs down the keel line.
Me (and my co-capt in the club) are very experienced sailors and fairly knowledgeable. We have racked our brains for 2+ years over this. Just when we think we've solved the mystery and have a dry boat for a while, the water comes back. We were CERTAIN is was a leaky waterline for a while, but we've ruled THAT out.
I was hoping someone w/ a C320 would see this and reply knowing how the liner goes in the boat.