There is clearly throttling being applied to my account. Without fail, each and every time I have an increase in traffic the cpc goes down to almost worthless levels.
I literally make more money when my sites get very little traffic.
There also seems to be a HUGE discrepancy in reported impressions. AwStats will show over a thousand uniques for a site while adsense will show maybe 100-150 impressions.
Some strange and shady things going on these last 6 months.