I'm having problems with one of my sites, i have a large rectangle box and only 2 ads show up on it leaving 3 big ugly empty spots. The strange thing is, only one of my sites have this problem, the other one is just fine. I use ad targeting to try to fill up the empty spots, but it doesn't work. Are you guys experiencing this problem?
I used to on a forum I owned (before I sold it). I don't know why or never tried to figure out why it happened.
Try switching the ad category, the problem you have may be due to less advertisers who target that category.
also, are you blocking any ads? I found that when I blocked ads that weren't related, it didn't refill with appropriate ads...so I unblocked. I would still rather have non-related than nothing and make my case to YPN