i recently bought a microgel prestige pro 1 month ago and i just got another today. The older one vibrates at the handle when dropped on the ground but the new one doesn't vibrate. In other words, the older one has a vibrating handle and the newer one doesn't have a virbating handle. Since the racquets were both new, i obviously took very good care of them and i nvr threw them or abused them. If one of the racquets has a vibrating handle and the other doesnt then that clearly shows that the quality of the older racquet is not ensured and hints that maybe there are other problems with it as well that i haven't yet noticed. What should i do to fix this problem? Send it back to head? If i do send it back, will they fix it?