tts mp3 not loading

[untold granite]

I'm experimenting with voice.
home assistant integration through music assistant.
When I run tts.speak - it works well. Radio streaming works well too.
But when using assist, it recognizes the voice, carries out action, but nothing plays back. Blue LED is blinking for like 10 seconds, but no audio.
From logs I see that my player can't load tts file:
http://192.168.69.4/api/tts_proxy/e2ELzasSf5q4JHfuG4HZkw.mp3

It does not load if I visit it with my browser.
Any ideas?

[untold granite]

the browser is "loading" without any error, but does not finish it. If I change the url slightly, I get a 404. So the file is there, it's just not loading somehow

[untold granite]

figured it out. My tts service was generating a corrupt file. Reconfigured it and now everything works.