kilz, is it named check6 for sure?  make sure it's not named check 6 with a space in-between.  One more thing, is it a check6 that came out of a soundpack, or one you found somewhere else?  If it is one of mine, let me know which one it is and I will double check its properties to make sure it's correct.  Let me know via PM or here.  If it's not one of mine, or the properties of it are wrong, I can email you a good one no prob.  Let me know.