What's with the Bell?

[Aargh-a-Knot]

Hi there. I just downloaded and set up Boxee. Seems to be a good app, apart from one thing. Every move I make with the keyboard, whether with the arrows, or hitting return, makes the sound of a Bell. Yes, a Bell. I went into the settings, and shut off the sounds, but no, the Bell is still there. If I turn the sounds on, there is also another sound present along with the Bell, turn it off, the other sound goes away, but the Bell remains. This is maddening! I see no other posts about the Bell, so I assume it's not a widespread issue. Anyone else having the Bell?

EDIT: I just figured out that the sound is whatever alert sound I have set in my system preferences. I changed it to basso or whatever, and now it makes that sound. WTF?

[im_electronic]

Boxee must be causing a system event notification, under sound try unchecking play user interface sounds.

[PHermas]

have you tried turning off navigation sounds?
settings>appearance>look and feel>navigation sounds