This is an unbelievable bug.
You do have to wonder how they test, it is someones job to go through all these use-cases and sign off the application as working. It doesn't.
There is a key for Play Fast (CTRL SHIFT + G) which WORKS under any circumstancebut (CTRL +) Right Arrow doesn't work.
It is as clear a bug as you could find and yet there is not even a response from MS.
Best solution is install VLC Media Player, this hasn't been fixed in 7 years so I guess they aren't ever going to.