It may just be some slack in the threads of the piece that is in the ball (excuse me I don't know the Vise names for each piece) and the IT insert.
I would check to see if it might be something like that or if the piece in the ball is acually moving.
If the piece in the ball is actually moving then get that fixed right away.
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18 mph,350 rpm,PAP 5 1/2 x 3/8up, 10-13 deg axis tilt, varied rotational axis deg.. usually 45+
HighGame 300 x 5, High Series 808
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