It depends on how the port was locked. If TTS locked the port than you can restart the AvTtsSvr service. If that doesn't free it up you will need to bounce Unity. Also, if port 2 is still registered and causing Call Forward No Answer (CFNA) to occur, you should upgrade to TSP 7.0(1) or later. It has new logic which will avoid that type of situation but the upgrade requires a reboot of course.
Hope that helps,
Keith