By the way, the only reason I am not using one of yours is mine came on the bow.I was trying the bow at the shop and got a couple of small slaps and theownerputs these on most of the bows he sells.
ORIGINAL: MeanV2
ORIGINAL: honcho12
Also you may want to try a string supressor. In a hunting situation from a tree stand you can't always get a good stance and have great form. I use onemade by shawnsarchery.com and am very pleased with it. I have a Guardian and I try to practice from different positions I might have in the stand and sometimes I would get the string slap too, but the string supressor cured it for me.
Although I don't advocate using a String Suppressor just to keep from getting slapped they will help
Make sure everything else is right and then add a String Suppressor and enjoy all the benefits.
Dan