sorry for your frustration, and I know this won't replace your lost balls... but here are a few thoughts.
I can't really dismiss whether the game is at fault or not, but I do think it is also possible other factors can influence a jumpy meter.
even though some claim the meter is smoother on the new version or mobile I have not always found that to be true... but here are some things I suspect can also potentially impact a fluctuating meter speed...
--- auto update of an app on mobile or tablet in the background that you can't see first hand, but ends up possibly being the factor that altered your meter and has nothing to do with WGT but rather your personal device.
--- a possible call on a phone
--- other processor related programs that unknowingly happen to pick up at inopportune times.
--- your internet provider experiencing heavier service or factors.
--- this does not include in game features or factors that may also apply or things the gaming algorithms may use
--- WGT may also use an occasional jumpy meter to test or evaluate if a player is using cheat software that may help them ding their shots but give WGT more insight into whether the player is cheating - I don't know but if this is the case, I can live with some random miss dings if WGT is catching people using cheat software.
either way, while some factors can possibly be built into the game - some can easily be device or personal computer related.