Just to verify that it is the rest, use some spray footpowder on the rest or some use lipstick to see if contact is being made. Sometimes you can get marks on the fletchings just from shooting groups with them. If you are in fact getting rest contact it may not be going down fast enough. Check that it comes to full up at the last inch of the draw, and on a TT rest there is a spring tension adjustment you can make inside it. There is one hole the end of the spring can go into to increase it's tension. A little tedious to do, but a little patience and it may be worth it to you. I did'nt have any trouble doing it with mine. I would check the contact first, then timing, then the spring. What is the drop-away cord attached to? Cable or slide?