If I am playing a HTML5 video in youtube in firefox, (usually just as background music) and I go around my computer doing various things like loading programs or saving text files, the video will stutter (the music will 'skip' like a machine gun sound like tron or the matrix is melting or something) and my mouse cursor will slow down during the skipping - and then it will go back to normal.
It lasts a second or two, and happens often enough to be annoying (it just happened when I typed the last word and then for a second it acted like I was holding down the spacebar but I wasn't.) I have a microsoft wireless keyboard, and this is on a toshiba laptop.
It will also do it even if I'm not touching the computer (but less), presumably because the computer is doing some automatic access thing like a file scan or something in the background.
(previously I piled this specific issue into another thread which was primarily about a different issue which I have now separately solved, but this issue remains so I figured it should go in its own thread)