The problem you describe is very common for Chrome browser users that have the PepperFlash version of Flash Player enabled, instead of using the ShockWave version of Flash Player.
WGT has no control over how your computer is configured or how your computer is maintained so it performs well for playing WGT, The meter plays on your computer. Indeed meter issues are almost entirely related to a player's computer.
Do you use a wired mouse or a wireless mouse?
Do you manage the power settings on your computer?
What browser do you you use?
What release/version of Flash Player do you use?
How many applications/services are running in the background on your computer? CPU usage during the down swing has a lot to do with how smoothly the meter performs on your computer. Smooth Meter
How many temporary internet files are stored on your computer when you have meter problems? How many cookies?