Help phone hangs at startup

[myliquid]

Hi,

I have a Liquid Metal (not rooted) which hangs on startup. The Acer logo displays as well as the Android screen. After that it goes black and a notification sound can be heard every 30 - 60s. When I connect it via USB to a PC the battery charging symbol is displayed.

I guess the sound wants to tell me something (hopefully more than 'it is broken'), but what?

Any help is appreciated.

Cheers