When you enter EyeTV's own onscreen menu, Remote Buddy switches to a special mode to allow navigation of the menu.

If it wasn't, you couldn't use up/down/left/right to vol+/vol-/ch+/ch-/rew/ff outside the menu and use the menu when it's on screen. In fact, if it wasn't, you could open and close the EyeTV's own menu, but you couldn't navigate it at all - you'd still only perform vol+/vol-/ch+/ch-/rew/ff.

=> Your mapping is only fully used when you're outside of EyeTV's own menu.

Best regards, 
Felix Schwarz