Rtmp And Rtmpt Protocol And Bitdefender Firewall

I've been trying to get NPR's streams but while it loads the window, the sound doesn't start. Reading the help files, it says the following:

A player window opens, but the audio doesn’t start. What should I do?

You may need to change your firewall settings to permit the NPR Media Player to stream by allowing access to the proper ports and protocols. (Please consult your network administrator or service provider). This may be the case, even if you are able to use audio or video on other sites, because different sites may deliver their media using different streaming methods.

What are the specific ports and protocols that the NPR Media Player uses?

The NPR Media Player attempts to connect to our servers over a variety of port/protocol combinations, and uses the first one that works. It first attempts ports 1935, 80 and 443 over the RTMP protocol, and then it attempts ports 80, 1935 and 443 over the RTMPT protocol. Consult your firewall documentation to allow access to these ports and protocols.

How do I set up the firewall (or see if it's already configured this way) to allow the streams? Thanks for your help.