Small diameter holes

Small diameter holes

I am having a hard time getting small diameter hole measurements. I am turning down the approach and back off parameters as low as they will go, and the probe will still crash into the other side of the whole as if I made no change.  I have tried local path, auto path, tried to use the seek hole, but it will always crash. Probe is 1.5 mm cylinder and I tried a 1mm ruby with the same results.