This kind of issue always comes down to DNS “stuff”.
side remark: there is IMHO no point in insisting in additional encryption, if you are streaming from a server in your home, over your own network, to a player device in the same home.
So, why not leaving ‘Secure Connections’ on ‘Preferred’?
If your router doesn’t have any configuration for DNS or ‘DNS rebinding protection’, this is what you’ll end up doing, anyway.
