Michael's likely correct... you might want to pull the brushes and take a look at them though if you got it new and haven't hardly used it, unless the brush is cracked, it shouldn't have work that fast. As for changing bearings, unless you can isolate a bearing as the problem it'll be a "buy and try", so find out the price of the bearings and decide if you want to gamble. I don't know about the UK, but bearings for both ends here could run anywhere from $20 to $75US. If that's the case, BJ's approach may be the wisest???
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