My media volume can't adjust in control center and AVRoutePickerView, only work when user click volume buttons on device

Question

I try to adjust my volume on my iPhone, Both AVRoutePickerView and control center can't adjust volume, only buttons on the left of my phone works.

Answer 1

From apple document, when we use AVAudioSessionCategoryPlayAndRecord in phone call apps, we can't adjust volume in control center or AVRoutePickerView by default.

https://developer.apple.com/library/archive/documentation/Audio/Conceptual/AudioSessionProgrammingGuide/AudioSessionCategoriesandModes/AudioSessionCategoriesandModes.html#//apple_ref/doc/uid/TP40007875-CH10-SW3