I am facing the same issue as David.
All my traffic (HTTP request) goes through port 37813 in debug or even normal mode. Strange thing is that sometimes it works immediately sometimes it takes a long time before it succeeds in opening the connection and getting an answer from my WS.
Does anyone know how to switch off the network monitor or how to make it working with Firefox or Safari (open the port ?)
I finally figured it out. In Flash Builder close your project. Then in the file system go and directly edit the .actionScriptProperties file. In the main <actionScriptProperties tag edit the includeNetmonSwc="true" flag to be includeNetmonSwc="false" instead. That will stop including the network monitor library in your code and should turn monitoring off.
That setting is controlled by the network monitor tab, but that tab is only visible with the premium version of Flash Builder so it seems once your trial version times out you can never disable it via the GUI, just via the .actionScriptProperties file.
Now reopen your project after saving the changes to .actionScriptProperties and you should be good to go.
Thanks a lot David, it will really save me a lot of time.
To complete your solution for other readers, the .actionScriptProperties file is in your project folder in the hidden file.
After changing the option, empty your cache and rebuild your project completely (change something).
Kishan, I guess people using the network manager in combination with Safari or Firefox on a local dev environment will not be satisfied with this solution. Any idea how to deblock this port ?