unusably noisy hoover nextra hnl 662?

my hoover nextra 662 is making a very load scraping banging noise as if something is stuck between the drum walls but seems clear.Drum rotates freely but seems to scrape on its way around, this builds up to a banging the faster it spins. It is unbalanced as the belt worked its way off and it now so loud it is unusable.Is it the bearings? I can't see a way to get to the drums, or take the seal off.