If your Dyson vacuum is emitting an unusual smell, see the Dyson Ball Animal Emits Unusual Smell or Noise problem page for possible causes and solutions. No guarantees, but mine was producing a loud screeching noise also. I removed the brush bar and cleaned the ends where it contacted/mounts in the head. I then used petroleum jelly (very, very lightly so as not to create a gunky mess) around these contact points where there is a lot of friction.