Turns out I'm having this problem as well, I just thought I was losing my mind! Last night I could barely hear my phone ring so I very deliberately set it to the max volume with the slider. Well, I just checked it in settings and it was set almost all the way down. Haven't had this phone longer than a month, running LP even less time, so who knows, but is it possible it has anything to do with Do Not Disturb mode? Mine's set from 12 midnight to 8 AM, but I just checked the settings at around 10:30. Do you use Do Not Disturb as well?
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