Problem with streaming from NAS to Smartphone

[MinimServerUser]

Good day,

I use BubbleUPnP and Minimserver to stream from my Asustor NAS to my Android smartphone Poco F3. This used to work well with Minimserver 1, but not anymore.

When I enter BubbleUPnP my IP: http://***.myasustor.com:58050
I can select my music in the library but cannot play it. The Bubbleupnp app simply stands still.

But if I specify the currently assigned IP address in bubbleupnp
http://46.128.252.73:58050
Then I can browse my library and play the music on my smartphone.

For testing in the Fritzbox 7490 Exposed Host set for IPv4 and IPv6 and DNS name server set to Cloudflare 1.1.1.1 doesn't help.

With AiMaster I can access my NAS.
Could the problem be with Minimserver v2?

Sorry, my english is not good, i translated with google.