v11 Animal cordless stick vac

I’ve seen many comments, here and elsewhere, regarding the brush turning for about 5 seconds, and then stopping. Most replies referred to cleaning the brush and brush head assembly.

I cleaned it, and took the whole head assembly apart, down to the motor, reassembled it - and it still stopped turning after about 5 seconds.

The motor arm is not held tightly, so I tried to get it to seat tighter but I couldn’t reduce the motion of the motor arm. And it doesn’t seem to move after the brush is in place over the motor arm.

Then I spun the brush while holding it by the mounting cover - and it wobbles - badly. I’m nearly certain that that is the problem. The motor spins the brush until the wobble causes it to shut off (I don’t know how this would make the motor arm stop, but it does)

I ordered a new brush and the first thing I’ll check is if it wobbles when I spin it.

I’ve never seen this as a question or in comments.

Have others found this causes the motor arm to shut off after about 5 seconds?

Are brushes supposed to be balanced?

Has anyone made it not wobble and fixed the problem?