Greetings,
Appreciate your patience. I don't hold much expertise in Azure media services. From the lab setup i found that "xxx-inct.streaming.media.azure.net" is the streaming endpoint host-name where is it automatically created using the input parameters. AFAIK, you should not use this hostname entry in the custom domain field instead you must first purchase one with a domain provider. For example, see Buy a custom domain name.
If you are using Azure to host your DNS domains, you must delegate the domain provider's domain name system (DNS) to an Azure DNS. Otherwise, if you are using a domain provider to handle your DNS domain, proceed to Create a CNAME DNS record. Automatic validation typically takes a few hours. If you don’t see your domain validated in 24 hours, open a support ticket.
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