[Darryl Ramm]

You need to start with standard troubleshooting, see the "Help us Help You" link up top of this web page. And describe exactly what try.

"Just Freeze" tells us nothing useful. What exactly you happens? Screen goes blank? Solid color? Mouse cursor stops or keeps working? All apps freeze or just Pro Tools? What do you have to do to get the system back?

Make sure no other apps are running.

In Console.app logs us there anything showing up around the time this happens?

Try treating the problem as a Pro Tools one (helps exclude some stuff...)

Always start with trashing prefs.

Make sure the playback engine is Built-In Output not an aggregate device. That is about as a reliable interface as you can get.

Then you are going to suspect plugins (because its easiest to check)... Are all plugins up to date? Temp. move all plugins out of their folder and start Pro Tools. Does that play through the problem area?

If that does not fix it it is likely a corrupt session. You can try a save In and see if that helps, but quite likely you are going to need to rebuild the session by hand.

If the client had this content as a Pro Tools session does it play OK on their system?

Is your system fully optimized?

You curiously misquote CPU clock rate but leave off anything actually useful to tell if your system is sufficient. Like exact iMac model, OS version, memory, specs of the disk drive you are recording to, wether you have a Fusion drive, how many audio tracks and what plugins and how many instances, etc. Much more info needed...

Disable ignore errors.... what exact AAE error gets thrown if any?