A benchtop spinning unit or a spare probe is useful to save both instrument time and risk exposure during spinning tests. A well-spinning rotor emits only a whirr. This helps the sample to settle into a balanced position. Do not override the automatic function of the spin controller. If it doesn't work, it's because there is a problem that should be corrected before proceeding.
Clean air is essential.
The tolerances and small air passages in the probe will not tolerate dirty air.