Help needed: Cast to HomePod not working

Hi, I have successfully added HomePod to Apple TV integration, however I can’t seem to cast to it, the aim is to use HomePod for TTS, which works on my phone, but when I try to cast to Homepod I got the error below:

Failed to perform the action media_player/play_media. HTTPConnectionPool(host=‘10.x.x.x’, port=8123): Max retries exceeded with url: /api/tts_proxy/4Uhglf65TSYpTGKqVYWCeA.mp3 (Caused by NewConnectionError(‘<urllib3.connection.HTTPConnection object at 0x7f25bbf5a580>: Failed to establish a new connection: [Errno 111] Connection refused’))

The HomePod is on a separate VLAN, however there is no firewall between and mdns is enabled. Does it use HTTP to cast? I also tried to play music to Homepod via HA without luck.

Any suggestion is appreciated!