Coleman tank leaking

[Gridlock]

Hey all,

I filled my hicapa mags today to store them for a bit, but when I took the AI Adaptor off the tank I could hear it hissing. I put the adaptor back on, it stopped, took it off and it started again. Worried, I pushed the tank gauge into the tip for a split second. It vented, then stopped. I couldn't hear anything nor smell anything, so I capped it and left it.

Anyone know what's going on? My initial thought is I messed up the tank O-ring somehow.

EDIT: I did find the 2006 thread pertaining to this same thing, but my problem seems just slightly different. Didn't want to necro a 3 year old thread either.

EDIT 2: So I'm going to assume after this many views without an answer that no one really knows what's going on. I guess I'll just keep doing what I'm doing.