Trust remote nb-5100 ctrl+F6 failure

Hi,
I bought the Trust notebook remote NB-5100p, an excellent product, except that BSPlayer uses for rewind function keyboard control+F6.
I can enter to remote configuration ctrl+F5 hotkey but not ctrl+f6.
I don't know why, I even checked it on another PC running w2k instead of win xp pro. Seems like a windows reserved key or something.
The problem itself isn't much to do with BSPlayer as I can't enter ctrl+f6 key also for media player or whatever other application.
Any ideas what's wrong with ctrl+F6?
Can I change a BSPlayer shortcuts?

John

[adicoto]

Probably it's assigned by a proprietary software. In here is all OK
In options->preferences->key assignement and winlirc you can assign any combination you want.