Are you sure it's not your computer?
Absolutely. This began after 1.2 and I know in my case the came cuts out at the end of Black Talon and Esseles but no other Flashpoint, all the way up to the end game level 50's. But even to this day both of those still "crash" at the end scene. In a group it's not so bad, you log back in and complete the mission. But it keeps you from ever running them alone.