I just bought a bearing. I spin it on my finger once and it spins for about 25 seconds. I spin it again and it starts making noises like one of the balls inside are bad. It only spun for about 7 seconds the second time.
Does it just need a cleaning?
Sure, why not. Otherwise, just play with it, it will work itself out.
How long have you had the bearing? It usually takes 1 - 2 weeks to break in the bearing. The situation you’re talking about suggests that there probably is something inside it. I would clean the bearing just to be safe before using it again. You don’t want a siezed/broken bearing.
Otherwise, the sound comes from the yoyo being dry.
Wash and lube is the solution.