My 4 yr old Seaquest Airsource inflator had a similar problem on a recent dive trip. After it began slowly "auto inflating", I snapped the button quickly a few times, & it temporarily subsided...only to start doing it again on a dive later in the day. A note worth mentioning here: after reaching ideal bouyancy @ a cruising depth of 60 -70 ft, I simply disconnected the LP hose & was good for most of the dive, occasionally breathing manually into the inflator. Dumping air as I ascended of course did not require the LP hose to be connected. I can certainly understand how a panicked diver could shoot to the surface without calmly figuring this out.
After getting the BC to the dive shop for service, it was simply a corroded schrader valve. The dive tech said this is common with ANY inflator hose that hasn't had ample rinsing. The last two week long trips I had done were liveaboards, which are notorious for not getting the "ample" rinsing it should have had. Cost of service & parts: $20.
