It seems they only say to require port 80.
Why can’t I launch a live broadcast?
authorize the sending of data to
live.radioking.com
via port 80
Why does my live broadcast cut regularly over a specific period of time?
poor internet connection (…)
it may be your firewall or antivirus (…) in which case you will have to (…) allow live.radioking.com on port 80 in outgoing connection.
The source IP addresses shown in the log appear to be from Apple and Rspamd.
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