My first question would be is your center serving starting to seperate at any point? If not then you said you have had this bow for 2 years. Your strings should be stretched by now. How much do you shoot throughout the year? Have you had the string replaced since you owned the bow. If not I might guess you may have some broken fibers in your string and your string might be starting to fail. If you haven't had your strings and cables replace since you got the bow I would. I usually replace my string every year and my cables every 2 years. And trust me it is worth the extra money to by a high quality set of strings and cables.