If you are using Windows...
Start the flash stream.
Open Windows Task manager's processes tab and look up the PIDs (Process Identifier) for:
Code:
FlashPlayerPlugin_11_602_168.exe (or similar)
plugin-container.exe
(To view all process PIDs select: View -> Select Column -> "check" PID)
Execute the Windows command
netstat:
Code:
netstat -n -o -p TCP
..and check the foreign address ports that match with the previously looked up PIDs.