Fuzzing is normal wear and tear on any bowstring. The amount of the fuzzies is a factor of the string material that was used in the string. Som materials just fuzz more than others. Zebras were made of 8125 until recently, and 8125 is notorious for fuzzing up a little bit. As long as what you are seeing is just the fuzzies, andnot cut strands, you are fine and continued shooting will not be a problem. Just keep waxing them to reduce the fuzies as much as you can.