Check if you break back wrist upon release. It might happen subconsciously, so a video or the eye of an experienced player will help. If you break it back too far, the track might rise, clipping the thumb hole or even moving as high as for a full roller, which normally runs between the thumb and finger holes. RPMs have little to do with this, and it also occurs regardless of the axis rotation.
Besides, the pooh is correct that either the ball can have a funky weight distribution, or the drilling makes it flare wrong, e. g. backwards. The latter could easily be the case, since the Cell core has a higher mass bias and its placement is vital for a proper ball reaction. Is the MB marker in or beyond the track area? This could be a potential source of the problem.
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DizzyFugu - Reporting from Germany
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