Trouble with Probe Head

[[Br...]]

I am having problems with our Contura G2 /VAST XT GOLD head.
It started last week when probing with a .5mm probe. When probing in the X+ (right) direction the probe would make contact then back off in the opposite direction without recording a point. If I would touch the head to get it going back in the correct direction it would then touch and record a point as it should. This also happens when scanning a circle. The problem also occurs with the 1mm probe. All the larger probes seem to work fine with the exception of a couple of times I had the same thing happen with the 2mm but it works fine most of the time. Attached are two pictures. One of the .5 scan and the other 2mm scan.
The probing force on the .5mm is set at 40mN and the 1mm at 100mN. All others are at 200mN. These have been unchanged for the past 5 years.
Without really knowing anything about how this works it seems as though there is a problem with the head not reading properly in the X direction.
I'm guessing that this is nothing I can fix and is going to require a service call if not a new VAST head.
Any ideas?

000-Point 5mm.JPG000-2mm.JPG