I was playing with it and found it's the valve not sealing. I opened the side plate and could push the valve stem up to stop the leaking. I took it apart and removed the valve. The culprit was the o-ring at the top of the valve. The o-ring was somewhat beat up. Like the place that it mates to isn't that smooth. It also didn't seem to have enough lube. I flipped the o_ring to get it to seat on the good side, lubed it up, put it back together, and it's fine now. I guess I will replace that o-ring if it happens again.