New Toto Toilet goes "bang"

[SeePlanet]

I saw a couple of other posts on this behavior, but curious about what the solution might be. I recently installed a new Toto toilet. Everything is running fine and has been for a number of months, but ever since the beginning when the water tank finished filling up, there has always been a large "thud" when the water is shut off. Apart from being a little jarring, is that bad for the plumbing? Any way to soften the water shut-off?

Here is a link to the recording of the thud -

The thud happens at about 1:09 in the video.

 

[Breplum]

add an angle stop water hammer arrestor, could help...and make sure house pressure is under 80