How to Check noise from right angle head when it rotates. (DCM , DBM , 90 angle Attachment head)

Situation :
Coupling looks ok, appears that it is not tooth-to-tooth when rotating.
Load goes from about 20% to 50% when head is rotating.
We are at Falcon Foundry today for noise with the right-angle clamps and when it rotates, it is very intermittent.
When it doesn’t have the noise load is at about 25 percent, with noise load is at about 75 percent.
We verified it seems to be fully unclamped when noise does happen, about .100” gap and noise is present.
If hitting feed hold when rotating, the noise is still present.
solution :
Need to check the female drive key parallel to Y-axis
If the keyways of parts #1 and #2 are not correct, unclamping will not be complete.
Adjust the #2 parts so that the keyway of the first part is parallel to the Y-axis.
The gap is 4 mm if the angle head is unclamp.

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