This is bound to be a bearing problem. Only a month old? Report it to the company/person you bought it off. Even if you bought it second hand, you stand up for your rights.
Even if it was sold 'as seen'- did it have a label saying the bearings were worn- because you can hardly give it a test at the point of sale.
Argue replace or money back-nothing less-dont delay
GB in Wales, March 2013