Occasionally, PhysicsControl controls will teleport to the world origin. This is sporadic and generally fixes itself either with a restart. In the licensee's case, the controls were also animation driven and returns to their correct places after a few frames.
Getting a stable repro for this is proving quite challenging.
Found once or twice in 5.3 ContentExamples in the 1.4 demo of PhysicsControl. Unfortunately, the repro rate is low, and attempts with a debugger attached didn't yield any results.
There's no existing public thread on this issue, so head over to Questions & Answers just mention UE-212986 in the post.