Like dave said, a good serving job will stop the sliding problem. Just a thought, make sure all your heads are either alligned with your fletches or try drawing back with a broadhead that has a blade pointed straight down. If that head clears your riser, your good to go. Another option is to go with a rest like the QAD, it locks in the up position and puts very little tention on the cord. Wont have any problems with blades clearing the riser either.