That makes sense.
But there's definitely something wrong with this app. If I close it manually and open it again without powering off the unit it still doesn't save the right position. But you are right, if I manually pause it before shutting down the unit it returns to the point where it was paused.
Before buying Poweramp I bought another music player app, n7player. This app returns to the exact song and exact location even after power off. The problem with it is that it takes foverer to start, and crushes very frequently. It also doesn't start playing the song automatically, I have to press the 'button', but that's the smallest problem.
So n7player is able to detect the shutdown/app close notification, but Poweramp isn't.
The music app that comes with the unit is fast and always restarts from the right point, but other than that it is absolutely ridiculous. Completely unusable.
So maybe I'll have to keep looking for some app that will work as expected.
Thank you for your help.