My vacuum is making a loud whirring sound and is hotter than normal.

\015 When the vacuum is on, it makes a very loud, fast, low pitched whirring sound in addition to the standard quieter vacuum noise. It almost sounds like a series of clicks. It also seems to be running hotter than usual. I've taken out the brush and it and the belt seem to be perfectly fine. I haven't noticed a difference in the cleaning abilities (though I stopped very soon after noticing the noise), but I'm afraid to continue using it until the problem has been solved...I noticed that it didn't make the noise when I first started it up or when I pushed it forward, but when I pulled it backwards it started and it continued when it was stationary. When I pulled out the hose to use an attachment the sound persisted. ..The side filter is clean and the dirt has been emptied. I just bought this vacuum a few months ago and it's barely been used, so it would be a shame if it can't be fixed.\015 – Bissell Cleanview Helix Bagless Upright Vacuum Cleanview Helix Bagless Upright Vacuum, 95P1