Well if that were not true then Apple would most likely not have released as public beta. Typically they go to 2-3 dev betas before releasing to public channel. That was the point I was making. Also a device (yours) or two that seem to have some problem as you describe but is not widespread and most likely not an iOS issue does not warrant deeming this not usable as a whole.
What have you tried to resolve a "no audio issue"? What device? If its pre 7 that has an old 3.5mm jack, it could be as simple as the contacts inside not going back normal close with the headset not plugged in.