Can you post the make and model number please.
Is it noisey when you turn it by hand?
What kind of noise is it?
Is it a scrapping noise?
This could be a faulty bearing at the back which is causeing the fault.
Take the bulged part off at the back and take off the heater unit. There you will see the drum shaft pin sticking through the back.
Check this and see what you find.
Let me know what you find or if you need anymore info.
Ok if you open the door and push the drum at the back and see if you will move up and down at the back.
Let me know.
Ok so the drum pin will be fine then.
So this may be either a faulty fan or a noisey motor.
But to find this out you will need to strip the dryer down from the front.
Then once its all striped down you can then check the motor and fan incase theres anything stuck in there.
But to get at it you need to take off the front control panel and then the front panel. Then there will be the front houseing unit which the drum runs round on.
Check this and if its fine then that will need to come off to get at the fan and motor.
But these hoovers are not the easyist to strip down and repair im afraid.
Ok i would say if a fan then about £70 roughly.
If motor then say about £130. But i would think its unlikely to be a motor.
What you can try is look in the yellow pages for a free callout company as they will check it out and if not worth the repair or its expensive it wont cost you anything to find out.