The thing chews up belts. There appears to be a misalignment of the drive spindle. I have replaced the roller and the floor/carpet idler clamp assembly. It appears that the belt is abrading against the (outer) lip on the drive spindle as it rides right next to the lip and the frazzled edge is over the lip. The spindle appears to be cylindrical. I have taken the thing apart (after I noted the apparent problem with the spindle) and can't see any way to adjust it. Any help? Thanks.