im on RN 13 4G with xiaomi.eu 2.0.12.0.
whenever im playing music/media the notification shows normally but when I turn off the device it appears for a split second and immediately disappears from the lock screen (it doesn't get removed/erased it just completely disappears with no animation) ...
I recently clean installed HyperOS 2 (a14) and noticed that phone was heating up too much in comparison to HyperOS 1. I checked the cpu clock speed and noticed that all the clusters were always running at max clock speed even when being on idle or no background apps.