[Rick]

I would pop out the bearings, and spacer. Then i would check to see it the bearings and spacer slides over the axle smooth out of the hub.
One or more bearings could not be seated squarely in the hub causing a mis alignment of the axle.
You may have a bad bearing on the drive side.

I make it a habit to pull the axles on a regular basis and clean and inspect. Stoch bite pads clean and polishing to ensure smooth operation.

Good luck