Shark Upright Vacuum Cleaner (Wilmslow SK9)

Shark powered lift away upright vacuum cleaner NV680UKT

Was working fine until the weekend, when it started to sound rough and the brush roller wouldn't rotate properly. I fully cleaned all the hair from the roller so that it could rotate, but it didn't sound much better and it smells like the motor has burnt out now.
Hopefully someone will know how to fix this and then it will be a decent refurbished vacuum cleaner again.