Loud beep after pressing MENU with iPod 5G 30GB

[Thunderpain]

Rockbox ver. 18162

It happens when I press Menu while there is nothing playing.  Before I press Menu though, there is no noise at all.  I press menu once, and a beep comes through the headphone jack.  Press it again and the beep gets louder.  As soon as I select a file and play it, the beep goes away.  It's a minor annoyance, but can be a real headache if I forget about it.  Any help is greatly appreciated