my guess bad belts inside or worse.
it needs service , some have clutches that go bad.
i see no free service manuals on it, so ask them?
clean the whole vacuum , end to end, first. inside.
then check for bad or worn sticking parts to the drive head.
or just find a shop to fix it. (any can)
Dyson will supply parts but don't provide manuals to their appliances (in the UK) but provide a fixed price repair service at a price they consider reasonable (I don't).
Dyson vacs are designed to manufacture as cheaply as possible, they aren't designed for easy repair or replacement of components. I haven't much experience of Dyson but the little I do have has taught me patience and a devious mind are prime requisites to dismantle...
Actually the hose is fine, but you really need to break it in... Dyson should have a robot at the factory break in the new hoses before shipping them with the new vacuums. I just got my first Dyson and it's an Ball Animal 2. Anyhow, I noticed immediately the new tube on the new vacuum was incredibly stiff. To the point that making use of the wand and attachments becomes a complete frustration.
Such an experience is not uncommon because engineers rarely dog food their own creation out of the box... Anyhow...
I had to stretch and massage my new hose aggressively for 20 minutes to get it to the point the vacuum wouldn't just flop over when I pulled it out. With the vacuum off I pinned it on the corner of the couch and maxed the hose out. Sitting 12 feet away watching TV I stretched and relaxed the hose over and over, pulling the full length a little harder every time. After 10 minutes of that I sat next to the vacuum and starting at the base of the hose, I aggressively stretched 3" of collapsed hose out to 12" with all my strength about 5 times like an accordion, over and over, before moving up to the next bit of hose. Repeat this workout the length of the hose. Now, I'm 6'6" and strong for a strong man, by the time I finished, the hose worked as seen in the marketing footage.
The brush is activated by the suction of the vacuum. If it stops spinning, that means that either there is a broken part inside housing that surrounds the brush, thereby lessening the power of the suction to spin the brush, OR there is a lot of debris, usually hair, trapped and tangled around the brush. That can cause a troubling amount of friction and cause it to stop spinning. Either way, you will need an Allen wrench set to open up the trigger head. I found this video on youtube which details how to do that. It's not my video, but it is helpful. https://www.youtube.com/watch?v=FwNDO3pUxzM
Odds are it's overheating and can't breathe. Check for clogs in the wands (they are very thin in diameter). They can also clog in the lower hose and/or the long hose you use for attachments. If all that is clear your filter could be clogged. But it definitely sounds like it's overheating.