Getting erratic rpm reading on the metering roller doing canola. Approximate readings from 5.8 back down to 2.7 then 1.1 then zero then repeat but may briefly hold steady. Usually run 1.1 to 1.2 Worked fine before running inoculant/soybeans. Replace a bearing on the metering roller but that didn't change. Switched sensors, no change. Going to clean all cable connections in the morning. Anyone ever had one of those metering drive systems apart ? What's in there ? when cranking by hand and holding onto the output side it does not appear to be slipping but need to know for sure as I don't want gaps in the field. Any help appreciated.