LX5-2-4T LX5 Bagless Cylinder

I bought this vaccuum cleaner having read positive reviews and also owning existing AEG appliances (a dishwasher and washing machine). Sorry to say, it has been very disappointing. The suction is excellent but no matter whether the brushes are up or down, moving the brush-head across a carpeted room is like "scraping" the floor even when the suction is turned down to the lowest setting. It is as though the suction is too high and the movement across the carpet is restricted because of it. Maybe due to having very small brush-head wheels? Also, when trying to vaccuum an obvious bit of fluff on the carpet, I can be going back and forth over it a number of times before it lifts it (or in some cases, I lift it myself!). Could this be due to no rotating brush in the brush-head? My old vaccuum picked up everything and the suction was probably less but it did a better job. Works OK on hard floors, but very frustratingly bad on carpets. Shame, it's a nice looking machine and a good build quality but in my case, I feel it's been an expensive mistake.