Unfortunately, I'm experiencing the same thing now. A few of my product sales have basically dropped into oblivion, even though my traffic is increasing (the traffic source hasn't changed at all). It gets a little fishy when you're making 2-3sales a day with around a 1:100 conversion rate, then nothing for weeks with a 1:10,000 conversion rate. I mean come on?
Over this last weekend, I had some friends buy my products through my affiliate links just to see if something was up (I paid them for it, and no I didn't get a refund - hence I wasn't ripping off the product owners), and guess what? only 30% of the sales were accounted for. What happened to my other sales? I'm seeing threads popping up everywhere with users experiencing the same thing. You'll get the occasional big honcho jumping in saying "sucks to be you guys, but my sales are fine," only to find out later he's getting the same clickbank runaround.
I've emailed clickbank about the issue several times with no response. In fact, a few minutes ago I signed up for a cool article submitter through my friends affiliate link so he could get credit for the referral. Think he got credit? Nope. Big surprise. That was the last straw and what what motivated me to create this thread actually.
So is clickbank ripping you off too? I'm in the process of migrating all of my sites to paydotcom or other affiliate sites. What do you guys think?