Pro Tools 11.2.1 Mavericks / Crashing during playback

Hey everyone. I'm just trying to mix some drums for my band it's becoming the biggest headache in my life because as more time passes more problems seem to arise for no reason...



I'm running a Early 2011 Macbook Pro, Mavericks 10.9.4, 16GB Ram Samsung EVO SSD



Pro Tools Native 11.2.1



MOTU 828 Mk3 USB 2 Interface



Media on an external OWC Firewire Drive



Running an external monitor off the mini display port on the Mac.





My problem is that my drum session which is about 9 tracks of audio running polyphonic elastic audio starts playing when i press play and then after about ten seconds it stops all the track levels freeze and I get a beach ball of doom staring into my soul and telling me to kill myself... I am so sick of the beach ball...



I reimported my audio into a new session (Same sample rate 44.1 and 24bit) and the problem persisted. I imported new tracks to move my audio too from a working session that I have thats a better mix to "transfer my mix" to this session and the problem yet again, after 10 seconds of playback freezes and breaks.



I've no idea what to do other than reinstall pro tools AGAIN...



any thoughts or similar problems?