I'm not an Adsense specialist at all, but I suggest you might give it a little time. Adsense learns how to improve the value of your ads because it understands

I'm not an Adsense specialist at all, but I suggest you might give it a little time. Adsense learns how to improve the value of your ads because it understands your visitors better over time. My Adsense income has increased 600% over time without me doing anything (still a small site, not enough to pay the rent, but nice extra). Of course other factors than just Adsense learning might have influenced it, too (ie more competition on ads or whatever), but still - my experience has been good.