Ok after the three found blocks today it looks like I am getting half of what is shown as the payout.
The payout hovers around .10 and it looks like I am receiving .048 as a payout after fees.
Although there are times I get .02 as a payout.
This seems to be a 50% decrease and not 8%.
I'm just guessing but the decrease is part of the answer it also looks like the pool has an increased hash rate. It could be smaller miners that do not show up on the list (there are more than 15 miners). The pool has produced 3 blocks in the last 24 hours when it was only averaging about 1.2 a day, either the pool has gotten very lucky or the hash rate has increased.
Also a network issue could have developed between you and the pool raising latency that could reduce the hash rate the pool receives (this is unlikely but possible). Not everything is nefarious just because your payouts are not the same.