My dog is the same and her spinning is inconsistent. Sometimes she spins; sometimes she does not. It is hard to fix an inconsistent issue. Her spinning can be before a jump or a tunnel. I can give her a series of verbal cues, a single verbal cue, physical cues, and never know what to expect. We have had four different excellent trainers and none know how to fix it. I have gone back to basics with a tunnel and a jump, taken basic tunnel/agility workshops, etc. and she continues. I can stand in front of a jump and ask her to jump and she does it perfectly. I can do it a second time and she spins. Fortunately she does not bark. She is very handler focused. We have been training for 2+ years.