Had this problem earlier this season, one of the QEV's was loose / busted.
Strip it right down and check the physical condition of the QEV's ( ie are they loose or broken at the thread ), if a problem I always send my EGO to planet for them to sort issues.
Laters
![Smile :) :)](data:image/gif;base64,R0lGODlhAQABAIAAAAAAAP///yH5BAEAAAAALAAAAAABAAEAAAIBRAA7)