Autotech position Transducer issues

We have a machine that uses the Autotech SAC-RL100 transducer. We have been fighting a problem for about 6 months that come's and go's.
The machine will run fine and not fault out with a stable RPM reading. Every now and then the RPM will start to jump around, (mostly higher than normal RPM readings). At that time we get the fault and shut down of position errors.
We have changed transducers, the clutch control, cabling to the transducer, checked the power supplying the clutch control many times over. Sometimes if I just unplug the transducer and plug it back in the RPM will be OK for 30 min, maybe the rest of the shift, maybe all day.
My question is, How do these work? Is there a way the voltage is changing ? What could be making the RPM become unstable? We have 18 machines all using the same setup and only having issues with this one.
Thank You for your input and knowledge.

Is this it?

http://www.autotechcontrols.net/resolvers/resolvers-size40.htm

A resolver is a transformer with a rotating winding and a fixed winding and uses an ac voltage to measure the angle...

https://en.wikipedia.org/wiki/Resolver_(electrical)

In a former life, I supported a bunch of machines each without a dozen of them and they were extremely durable and reliable. We were using the HT100 by AMCI which is built like a tank. Even though those machines were wired nasty and subject to constant pounding vibration, I only had to fix an occasionally broken connector when someone decided to use the cables for a rope to climb with.

I heard rumors of the possibility of electrical noise being able to cause interference, but never saw it first hand...My resolver decoder modules were in a PLC-5 (also built like a tank)...

In your shoes, since you have ruled out the device itself, rule out the cable and the module to which is is connected next in order of which is easiest to replace.

Yes thats the resolver we are using.
We have taken parts from a working machine and moved them, will not work , (completely), we have changed cables for one point to the other. These feed a clutch control module. Replaced with a new one, no help. We have checked grounding, unhooked grounding, added grounding. All with no long term fix. I have called and chatted with Autotech to get there input as well but they where not aware of anything like this before. There still looking into what could be the problem.