I have checked loads, I have done the following.
1. took cone out and blew dust out with compressed air.
2. washed filters
3. checked pipes for blockages
4. checked rubber seals
5. checked brush bar for hair
6 checked bush bar and does spin.
suction from the wand is second to none, I picked up a heavy weight with no problem.
I either need new filters (can't see that being the main cause?)
took flexi hose off, filled with water, no leaks.
I have considered, dyson call out or buying the dc33
there is no resistance whan pushing along I am sure it used to suck the carpet, it still picks up, i sprinkled flour on the floor and it picked that up