I did a search and found where others are having the same issue as I am with these soft caps. Because I was getting some leakage into the vapor path, i.e. through the mouthpiece, I replaced the hard plastic (nylon?) cap with a soft one I got today. Instant burnt paper taste. Before the switch: great taste.
My search didn't turn up a viable solution, though.
Is there some trick to using these soft tank caps, some method of preparing them so they work properly? I believe I'd rather put up with getting a bit of ejuice in my mouth than that funky taste these silicone caps impart to the vapor.
My search didn't turn up a viable solution, though.