when i pull the bow back,the sound does not happen...when i letoff,it makes a cracking sound,it is the cable guard....what can i do to stop the sound.....

Maybe try cleaning it with alcohol or replacing it with a new teflon slide,,,, after checking it for cracks if it's an all carbon rod.

bobcat 10,
Mine did the same thing after shooting it most of last Summer. Either replace it with a teflon slide or take the original off and clean it. They wear a little and get a plastic residue on the inside. Just clean it off. Don't put any kind of lube on it though! They're meant to slide dry. Hope this helps ya!

Good Luck,
John