Showing Low Hashrate on Pool

[abbtech]

I have a Butterfly Labs 30 GH/s machine and I am running easyminer. Easyminer shows a hashrate of around 28 to 30 GH/s but eclipse mining consortium (the pool I use) only shows around 22GH/s. It has only been running for about 4 days and at the beginning it both numbers jived but all day today the pool is indicating low. Which one is correct? Am I loosing out on 8GH/s somewhere?

[RW02]

the pool calculates it on how many shares you submit and how many are accepted

easy miner i think counts all shares both rejected and accepted
it could be down to a bad internet connection with a high ping
but more likely its lack of cooling causing the chips to overheat a throttle back
make sure theres room around the miner and that its got good airflow
then if it still happens try disconecting the miner and letting it cool so the case is cold then plug it back in and see if its back to normal
if that dosnt work use a newer version of cgminer id recommend 3.5