Power Heads on Vacuum Cleaners - ideas?

Okay, I AM going to call my vacuum guys tomorrow. But I thought I would see what someone else thought.

I have an Electrolux AP280. It has been reconditioned by the vacuum guys, and has a one year warranty. So that is not a problem.

I LOVE this vacuum - got it about 1 1/2 months ago. Canister (similar to the Olympia model in the USA, I understand).

Power head. Last time I used the vacuum, I accidentally sucked up a sock. Took it out, hit the reset button for the power head, and everything was fine for the rest of the cleaning.

Today - it kept stopping every couple of minutes. I'd hit reset, and it would run another minute. Thicker rug REALLY messed it up - if I lifted the head off the floor, it would run power head like nothing.

??? Anyone deal with this before? There's nothing jammed in the beater bar...

Thanks.