Silicone seals. Thanks all. I will check for leaks. I changed to new seals right before my last test dive so if I do have tears this system is crazy easy to tear. I will also check for damage as suggested. Glad to hear they work well for everyone else. I have read nothing but good things. Just frustrating to be the 1% that has the issue. Hoping to find a solution.
I've been wanting to reply on this for two days... Slammed at work.
Firstly, you're doing great to leak test your suit, but there's a better, more reliable way. I'll make a video at some point when I've got a leak that needs to be diagnosed, but meanwhile, here's the process:
In short, the suit needs to be tested inside-out - because the problem isn't that you've got air leaking out, it's that you've got water coming IN. Often times a hole in a suit will only flow in one direction - it'll close in the other direction. Thus, any leak tests of air flowing OUT of the suit may or may not be accurate.
1. Remove the inflator valve from the suit and install it backwards. The button should be mounted on the inside, and the vent/filter should be mounted on the outside.
2. Block the wrists. I like to snap on my drygloves, but if you don't wear drygloves (yet), cups or soup cans work fine.
3. Turn the suit inside-out. Do the best that you can with the boots, if your suit is equipped with them.
4. Place the suit on it's back in the grass.
5. Put a scuba tank inside the suit with the valve sticking out of the neck hole. The neck seal should seal around the scuba tank. Zip the suit up. It's a little complicated to do with the zipper pull now located inside the suit, but you can do it if you're patient.
6. Connect your first stage to the tank and to the inflator valve. Inflate the suit. I like to run some painter's tape around the neck seal to help keep the pressure inside the suit high.
7. Use a spray bottle filled with soapy water on the area that you suspect is leaking. You'll see bubbles where the leak is. Mark the leak with a grease pen or magic marker.
8. Cleaning up is easy... Rinse with a hose, open the suit and disassemble the tank and regulator. Hang inside-out to dry overnight. Once dry, turn rightside-out again, reverse the inflator valve, and hang to dry the outside of the suit.
9. Develop a solution to fix the leak.
This procedure is the ONLY way that I've been able to reliably find water leaking INTO the suit.