Keymap Problem keyboard.xml

Hello,

in the standard keyboard.xml in the subsection FullscreenVideo the commands AspectRatio is assigned to Key Z, ShowSubtitles to T, NextSubtitle to L.
I created my own keyboard.xml to use with my Harmony 300 as a MCE Keyboard and assignd the commands to other keys as follow:

AspectRatio to R
ShowSubtitles to G
NextSubtitle to Y

and now i have the Problem if i push R the AspectRatio changes, this is fine, but if i push Y the AspectRatio changes too.
It is equal i press the harmony button i assigned or the key on the keyboard
I have no idea why. There are known problems with key remaps?

Thanks for your Help

PS: I use Frodo RC3. I test it under Win7Pro and Win8Pro.