First of all, welcome to the Village. Now, as to your problem, we might need a bit more info. And pics are always helpful. So, what brand/type of saw do you have, what blades and what wood? These all need to be answered. I know that I will hear different sounds when I'm cutting with or across the grain but not to the extent that you mention. Please add on here and we'll try to help. And the answer/s might help someone else who has had the same experience.