Sorry for the delay in getting back to you on this one. I've been sitting here trying to work out what the problem is. The bluetooth dongle is 0.5 meters away from the mouse and there is nothing in the way and the rechargeable batteries are new. There are no other 2.4GHz sources nearby - a wifi source is 10m away. I still have the same issue. The juddering is always there when I start the machine. I use just firefox, thunderbird and netbeans. Sometimes the juddering stops after a couple of hours, somethimes after 6 hours, most of the time it's still there at 7pm when I turn off the machine for the day. When browsing, this isn't an issue. When editing code and trying to place the cursor at an exact spot in the editor and then the cursor jumps away from the correct spot (just as I'm clicking for insertion) - this is a real pain. But, if no one else is experiancing this then it must be related to the way I originally set up the machine (nothing fancy, just a regular/vanilla install). > From: