I seldom post here but I think this might be worth posting. I have had a pair of less than 1 year old rackets (AT600 & Cab35) and both developed cracking sound inside the cones. I am familiar with loose cones and had to reglued all my MIJ Yonex rackets the last 2 decades, including the AT600. The cracking sound of my Cab35 has developed to a point I have decided to reglue it with epoxy, and this is what I have found. From what I can tell, the gaps of these cracks are so wide they should be spotted in the factory. Obviously the worker decided to glue it over instead of trashing the wooden grip. I have learn from experience MIJ Yonex aren't as great as most have praised, but this is new low, and certainly deter me from buying in the future. Hopefully the shop won't give me a hard claiming the 1 year warranty which still has 1 month to go. Also, I have discovered the cones of both AT600 & Cab35 are glued on one side only. I can tell they simply squeezed a large drop of glue on one spot then put the cone on. IMHO, this is very poor practice because the cones will never provide the full support the wooden tip needs when stressed. The glue should fully fill the gap between the cone and the wooden tip. No wonder there are so many broken grips over the years which can be avoided if Yonex Japan did their homework.