Ad reviews
Review ads currently cycling through your site. Remove ads you feel might turn off your visitors or might not be the best fit for your site or visitors.

Experiment with ad sizes
Give your ad units specific names. Track their earnings. Try different configurations. However don't go overboard above the fold.

HTTPS bug
Not sure if this has been fixed. But it was reported that switching to HTTPS may cause the auction to collapse because of a lack of suitable secure landing pages for ads.

Research your niche
Has your niche changed? Not all niches are evergreen. Technologies change or are replaced by different ones. Seasons, social, sporting, political and weather events can cause a change in surfing habits.

For what's its worth, I blocked Interest ads and Third Party ads - and saw an immediate increase over the last few hours regarding my revenue and my RMP has stabilized. Whether or not that will continue remains to be seen.

hmm for me 3rd party and interest based have the best stats for me.

You need to test for a reasonable period of time - I never test for less than a week, and prefer two.

I've tried "controlling" ads, I've left G to serve up whatever it likes, I never found any difference whatsoever, YMMV!

I've blocked ads on my site in the past. My experience is that while CTR might go up, CPC tends to go down. I also suspect that what you earn has very little to do with who clicks what, but that's just my opinion.

Adsense has been dreadful this year. I'm getting some of my lowest numbers in 18 months, but traffic is higher than ever.

One of my buddies is down 48,000 this year, compared to last year, with his Adsense. And the rep he deals with cant figure out a solution to make the bleeding stop.

I wonder if I should take a chance and contact Adsense regarding a banned section.

Four years ago, Adsense stopped serving ads to our forum. For whatever reason they blocked ad severing to that section of the website, likely after it was hacked.

I never contacted them, as I was making a six figure income off of Adsense and was basically relieved that our main url was still serving strong and so were other sections of the site, other than the forum section.

Now that four years have passed, just celebrated my 11th year with Adsense, I wonder if it's time to contact them and see if they would be willing to remove the ban from my forum area.

Link units at the bottom of an article tend to do well for me.

Why not , contacting G support just for asking, worst thing they'd say you still can't show ads in the forum, their not the gestapo..

Actually, they are the Gestapo. The worst case is they will look at your forum and review your main site . And if they see some thing that violates their TOS, they'll ban your main site too. My hunch tells me there is something in your main site you don't want them to see.

They just reviewed my main site a few months ago. One of those random checkups every few years. The complained one ad was too close to one of our sponsor images, even though the sponsor logo possessed no link and couldn't possibly produce an accidental link. Regardless, I moved the ad by "half an inch" and that was enough to satisfy them.