"I have the Dyson Animal DC07 - about 6 years old. When using the vacuum (not hose) it is not cleaning the carpet - it still picks up hair (cat) but is leaving small particles, etc. Sometimes have to almost hold the vacuum up straight. Tried using the hardwood floor feature it didn't work well either. replaced the small hose under the machine and the main hose good shape - should I replace the brush? Thanks "