I'm not sure how common this is or even if anyone else has noticed this but I found an interesting issue with my 8310. I believe it has to due with the fact that I have BlueTooth enabled, not for discovery of course, but to enable me to click open my DM and with another couple clicks, I can sync and backup my BB without even taking it out of the holster on my belt. Very convenient but when I do pull it out and set it on the desk with my computer, I found that if it is within a foot or two of my keyboard and mouse, I get very strange issues.
The keyboard will just skip letters while you are typing and the mouse will get lazy and become very stubborn. Both the keyboard and mouse are wireless but not Bluetooth. They use their own special receiver mounted behind the monitor. But I don't think that receiver and my BB get along very well. Move the BB another couple feet away and all is well.
Just in case you thought the batteries were going dead or something.