Logic 9 response so slow after Mavericks update!

Hi guys! Ever since updating to Mavericks the response time when adjusting parameters on synths and plug ins with in Logic are extremely slow, arranging is fine, its just when i start eqing, using delays, adjusting synths etc, audio will still play but can’t stop it or adjust anything for upto minutes sometimes. Im running 2.8 ghzs core duo, 4 gb of ram. Was pretty smooth before i updated, any ideas would be very much appreciated, will be doubling my ram soon too. Thanks