Web Audio on iOS

I try to setup web audio for my wall mounted iPad.

Server is on v4.1.1

Client: iPad (iOS 17.2)
Enable Web Audio sink support is activated
Tested on chrome browser, safari browser and openhab App (v2.4.56) without luck

Web audio on android device or Windows browser is no problem.

According to this ticket it is supposed to work on OH3.

Anyody has a hint or could confirm it is working?