if it was eX, I was going to say it's a built in feature.

Gotta hate that leaky hatch. But you gotta love it for storage.
I still love my eX, sorry.
It sounds like a leak. Get it fixed it or get a new one. Not safe for operating if it's that consistent.
Fill it up with water and put on a dry surface. Never tried, but often read about folks doing that. See if, and where, the water is coming from.
Have a water pump on board if you have to go out, have a radio.
Carry a sponge - works great.
Not to say it is bad idea to have all these things on board even on a perfectly tight and healthy kayak.