Ever since I updated by iphone to the IOS18 Public Beta 1 my volume has been stuck at 100% and the bar has been greyed out, this caused many apps to become mute, like duolingo and instagram. Youtube would work fine as well as a few other apps, but most of the time I had no volume. After what feels like ages, the solution was to simply turn off "Vocal Shortcuts", there seems to be a big problem with the vocal shortcuts controlling your volume which makes some apps that take microphone inputs just break. I will attach an image of what my volume looked like most of the time below:
Volume stuck at 100% with a greyed out volume bar.
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