Thanks myuncle, i appreciate your help. I have already tried this link ... and i've turned off new Beta Updates. I then completely Erased and Restored old data - but still have iOS 17.4 beta as the OS. I can't find a way to revert to iOS 17.3.1, so i wonder if i'm not actually able to do this. Maybe some data on iOS 17.4 isn't backwards compatible? Any idea what i'm doing wrong or what else can be done? Thanks !

Yep, I am also experiencing same problem. Audio played ok in iOS 17.3 but no longer plays in 17.4 beta 1 or beta 2 on iPhone 12 Pro & iPhone SE v2. It's a problem in Safari, Chrome & Firefox iPhone apps. Not been able to test on iPad as i don't own one. I have reported to Apple via Feedback App - but Apple rarely answer or seem to listen to developers reports. Feedback from Apple would be helpful to us all, as we try to earn money from apps. It would also help improve Apple's relationships with developers. I do hope this fix this soon, as they have broken the internet!

Still broken or is there any solution yet? It seems Apple have really thrown a spanner in the works and broken Google Cardboard VR and Unity in iOS 14. It’s now 14.4.1 and still no fix from what I understand. This is very well known issue ... why has it not been addressed yet by Apple developers? Anyone?