I wonder if this is related to the volume bug in iOS18 that got worse in beta 3. i have noticed when you open an app that has audio it will work at first but if the app gets interpreted by anything (Ads / Notifications) or if you leave the app to switch to another then the audio will just stop. Since it seems to effect all apps it could be what is happening here, or even carplay is adding to it.
OSBeta87
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