This morning, something weird happened. I set up the alarm to wake me up in the morning, and it did, but silently. Problem is that ringer was set at 50 percent, so it shouldn’t have been this way. I always set it up this way, and it always worked. Except this morning. Luckily, I woke up 10 minutes after the alarm on my own. I could have been really late for work. For the record, I didn’t have “Do not disturb” turned on, if that matters. Ringer volume was set at 50 percent, media volume was set at 0. But this should not matter, because I did this same before, and alarm sounded normally. When I woke up and realized what happened, I tried to find out what was the cause. I increased the both volumes to 100 percent. Nothing. I couldn’t hear lock sound first. Then I opened YouTube to play some song. Still nothing. Complete silence. Restart was the last resort, and it solved the problem. Everything is fine now. It looks to me like this is some sort of bug, and I do not know how to replicate it. I just went to sleep, and didn’t do nothing, so I do not know how it happened. I am using XS Max, btw, with iOS 12.2.