Same here...Have been having the same issues as you guys. I'm able to join small game modes (Cargo, Hero hunt) but not big game modes (Supremacy, Walker Assault).
Have tried port forwarding, clearing DNS cache and "test connection" method with limited success.
I am getting extremely frustrated and would really like to hear from EA about this issue (even if it's just they're aware of it and working on it)
However, one method has been working consistently for me: If you have a friend who's online (you may need to party up with them) select their avatar in the top left corner of the screen. Select "Join Game". It'll take you through the loading screen (you may need to wait in queue) but instead of booting you out and giving the "You have lost connection to playstation network", you should progress to the load out menu.
Hope this helps some of you.
EA, please at least acknowledge that you're aware of this problem. Lots of people paid hard earned money for you product. Thank you.
