Is it possible to chnge/set default volume settings?

[Bataar]

Every time my phone restarts (Lumia 1520), my volume settings get changed back to whatever the default is. This is a problem because oftentimes, I won't know that the phone has restarted so I'll press the button my headset to make a call while I'm driving and the volume will be so low I won't be able to hear anything. I hate to have to fish the phone out of my pocket while I'm driving so I can adjust the volume so I can hear.

 

[dKp1977]

There's no way to set a default volume level anywhere. I'm not even sure it doesn't keep the last used levels, as I never paid any attention to it. What I know for sure is, that it doesn't keep the headphones volume settings when rebooting.
Nevertheless, if your phone tends to reboot on its own regularly, it no doubt has some issues. I doubt a simple soft reset or even a hard reset could fix that, as I believe this is hardware related. But it's certainly worth trying out. If neither helps, send it in for repair.