Flush is too strong?!

I've got a weird question for you...

What can I do with a power assist, rear flush toilet that suddenly is flushing too strong? The toilet is about ten years old, and worked fine until a few days ago.

Now, the water hits the bowl with such force that it kicks out onto the floor. Is there some handyman friendly adjustment, or should I call a plumber?

(A pleasant change of pace... you don't see too many people complaining about a toilet flushing too strong!)

Has the system water pressure changed recently? Or, if you have a PRV, could it have failed, raising the system pressure? Sometimes the city does some maintenance or switches things around and they up the supply pressure. You can pick up a water pressure gauge for about $10 at a big box store or a plumbing supply house. It generally comes with a hose type connection you can screw on, or with adapters, most anywhere else, like on a faucet after taking off the aerator.

I gave it the "eyeball" check when I swung by this afternoon (i.e. turned on the shower and faucet and looked at the water flow), and it all seemed normal. I probably have one of those pressure testers in my shed... I'll give it a test tomorrow. Thanks!