Recently my ringtone has been set to maximum volume on its own. Does someone have the problem or tips? iOS 13.2.3.In the control center, the volume is set to approx. 1/3, but when I press the Volume Up / Down buttons it is at full volume and the volume also rings. If I make it quieter, after a while the volume will turn up again by itself, whereby 1/3 is still displayed in the control center.