The bogus or spoofed Referrer URL issue is back. It just started up again this morning as best as I can tell. I reported this issue the first time in September 2016. Several emails and three days later they were able to replicate the issue, and a few days after that it was fixed, till now.
On my hiking site, TrailsNH.com I use the Custom Tracking Code (CTC) of “homepage-merchants” on logos for my most active merchants. These logos only show on the homepage, and I do not use CTC=”homepage-merchants” on any other affiliate impressions. Yet, 7 out of 8 URLs are not from my homepage, 5 of those do not even refer to my site.