Ive played extinction for hours on end only until recently after downloading awakening my ps3 just shuts off in the middle of a game. My ps3 is not over- heating because I can play other games for hours with no problem. I have been told that the graphics for ghost is too demanding for ps3 which is false because I had no other problems with this before. Any ideas?
With this issue, I'm thinking that this might have something to do with the internal system of your PS3 since you downloaded another DLC that will use up your internal memory. What I can suggest is that you try Rebuilding Database of your PS3 by following the steps from this link: Safe Mode on PS3
Or if that didn't work, you can also try port forwarding sine this is happening when you're playing online: Activision Support (Port Forward and NAT FAQ).
Hope these suggestion helps.