In the FWIT department I think the majority of the meter problems are twofold.
In my own experience Flash is a WELL KNOWN memory and CPU bandwidth hog!
Combine that with an inferior mouse and you have a recipe for meter failure.
I have been fighting meter issues since I started here same as the rest of you. It comes and goes, no pattern, can't get it to stabilize.
I had been using a Logitech wireless programmable mouse for years (Even played World of Warcraft and Call of Duty with no problems) so I thought try a wired mouse, no luck.
So here is the issue as I have come to understand it.
The polling rate on the mouse and the CPU bandwidth required by flash create a conflict and the result is a jittery meter.
The solution for me was $35 Logitech gaming mouse, the G400 and Logitech Gaming software.
I have the mouse setup in the software for 400DPI resolution and the polling rate set to 1000.
I have been using this mouse for almost 2 weeks now and have not had a single meter issue.
Not saying this would solve all the meter issues but it is one thing to look into.
And yes I do clear the cache, use Comodo exclusively for WGT, use Game Booster, close other browser windows, etc.....
and it was the Mouse that finally resolved my issues.