sponsors don't "shave" anymore, they just use software to "evaluate" the productivity & profitability of your traffic & if it isn't making a certain amount more than they are paying for it, they just don't report that you ever sent the signup. simple... basically, they are putting the burden of "finding" their money rather on the webmaster rather than accepting the responsibility that is up to THEM how much money they make from your traffic (they make money whether u send signups or not so.... strange concept).".
from Smut Peddler Blog
http://www.smutpeddlerblog.com/archives/00000064.htm
I am going through the same thing with Lightspeedcash. Time to drop them.