System memory issue ... OS X

[SPC]

I'm having a problem with a Playback Engine issue in version 6.0.1. In the DAE Playback Buffer when I have the "size" Level on anything greater than Level 0, I get; "REQUIRES xxMB OF SYSTEM MEMORY. YOU HAVE 5MB ALLOCATED. A RESTART IS REQUIRED". The only way I'm able to get past that is setting the DAE Playback Buffer to 0 because it always says YOU HAVE 5MB ALLOCATED no matter what I set the buffer level to. I get "Pro Tools was unable to adjust your system memory settings, you must have a valid admin password to change these settings". How do I get that system memory to increase?
FYI the "Minimize system memory allocation (takes effect at next restart) is always greyed out.

How can I fix this problem?

Can you tell me what the Mix TDM Settings should be set to:
H/W Buffer Size?
CPU Usage Limit?
Can these setting be a part of solving the problem?

Thank you,
Shawn Conrad

G4 450, 768ram
OS X 10.2.6
Pro Tools version 6.0.1 Mix Plus (Core and Farm)
seperate Audio and video firewire drives
USD
888/24

[thomoose]

never done any PT in X, but it sounds like a permissions thing. Are you logged in as a user with Admin priveledges?

'best
Tom