Depends on the BB. If it's sealed, there's not much you can do besides replace it. If it service-able, then dis-assemble, clean and re-grease. Check for play also...another indicator that it's wearing out.
Is it possible that it's one of your pedals?
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2014 Specialized Roubaix2003 Interloc Impala2007 ParkPre Image C6 (RIP)