System responce is very slow

[Jstil]

I am currently having issues with PT HD 7.2cs2. My system seems to lag every time I try to do a task, for example when I try to save my session it seems to take a while(5-7seconds) and the file drop down menu stays hi-lighted this whole time.

Other tasks such as soloing a track, setting a track to input and record ready, and changing inputs and outputs of a track seems to cause the spinning beach ball to appear for a few seconds before completing the task.

I am using very few plug-ins (about 7 TDM)

My current playback engine settings are as follows:
H/W buffer size: 1024MB
RTAS Processors: 1
CPU Usage: 75%
Voice Allocation: 96 voices
Delay Compensation: None
DAE Playback Buffer: Level 2

System:
PTHD 7.2cs2
HD 3
Dual 2.0GHz G5
8G memory


Any help would be great. Thanks