Can't say this will solves everyone's meter probs, but it has for a couple of guys in my CC, so I thought it was worth sharing.
Both were having the "normal" jittery meter, but it seemed to have got worse recently, to the point of becoming unplayable. After a lot of guesswork, one of them mentioned that he had checked his Bios (?) and the CPU was running a bit hot. He planned to try a new fans and various other options.
I (half jokingly) said "stick a fan in front of it". Well he did. He took the side panel off the PC, and aimed a desk fan at it. MIRACLE! Meter was smooth as silk. Fan off - jittery again. Fan on - smooth again within 60 seconds.
Inspired by this, another member tried the same, and got the same result.
Now I'm no techy, and I'm not saying this is the answer for every ill that WGT can throw at us, but I do know that PCs like to be kept cool, so if yours is giving you grief, this might be a simple cure for some problems.
Steve.