This only applies to the HTML5 audio player with the public IP address. There is no need to Port Forward for the HTML5 audio player with the private IP address. If the HTML5 audio player with the public IP address will not play on a computer outside of your network, there is most probably a firewall on your computer or network blocking the connection. To know for certain if a firewall is blocking the traffic, simply turn off every firewall on your computer and in your network, and then try to listen to the internet radio from a computer outside your network. Don't forget that Anti-Virus software such as Norton, McAfee, AVG, Kaspersky, Baracudda, Webroot, TrendAnywhere, Spybot, CCleaner, Malwarebyes, all can have their own firewalls. If the HTML5 audio player with the public IP address works when the firewalls are off, but doesn't work when the firewalls are on, then a firewall on your computer or router or modem is blocking the traffic. Once you find the firewall that is blocking the traffic, add an inbound exception to that firewall to allow the inbound traffic on port you have declared in your Icecast.xml file.