My DE filter seems to be sending de into the pool through the return jets after bumping. I also noticed that I hear a funky noise coming from the top of the de filter cover when water rushes in, it almost sounds like rocks or something.

I know there are no rocks in there but thats what it sounds like. I took the filter apart, cleaned the filters, checked the plates for cracks and put it back together and I'm still getting that sound and de in the pool.

The good thing is that it only shoots out de for about 10 seconds and then the water from the return runs clear again.

Ideas?