Hello everyone, im somewhat baffled, my top performing keyword on google adwords has for the last 6 months had a quality score of 10/10 :-) an average position of 2 :-) and a max cpc of 22 pence giving a average cpc of 18 pence. The website is updated regulary and is alos high in organic serps, and all my other google adword keywords ( 4000 of them ) are nearly all 10/10 so google likes me but ....

yesterday the max cpc went from 22 pence to showing ( min bid 38p below first page bid) not i upped it but the average cpc went too high so i put it back down but it still wants min 38 per click.

The quality score is still 10/10, the av position is still 2 and there is no new competition

I do tweak my campaign regulary sometimes tweaking 100's keywords at once, i dont know if this would affect it

any ideas would be greatly helpful as im really stuck on this one

thank you everyone