this has happened to me several time with different USB Optical mice, but just to explain my problem i'll use the Logitech iFeel Mouse USB as an example. During normal use, the mouse cursor will freeze and i'll hear the Disconnected Device sound, a second later i'll hear the Device Connected sound followed by the cursor moving again. What i'm trying t say is that my mouse more or less seems like it is being unplugged and plugged back in quickly. Any Ideas?

hey, you might wanna check out this thread over at anandtech:
http://forums.anandtech.com/messageview.cfm?catid=38&threadid=641423