I see that you use fixed difficulty. For instance, if you start on diff 500, you constantly stay at 500. Other pools have a more dynamic approach. Is there a way I can increase diff manually? My GPU on diff 10000 sends your pool hashes every 6.4 seconds, my CPU on diff 5000 sends every 14.5 seconds... on official pool, my CPU stabilizes around dif 30000 and my GPU around 150000.