Allrighty, so that’s indeed the same issue.
Since you have already tried the workarounds and your setup is apparently pretty standard maybe a logcat could reveal some additional information. Are you familiar with adb? If you aren’t, you can follow the first two steps of this guide.
Afterwards run:
$ adb shell "logcat -c && logcat > /sdcard/logcat.txt"- Try changing the ringtone in the settings and wait for it to crash
- Press Ctrl+C in the terminal you have
adbrunning $ adb pull /sdcard/logcat.txt- Upload
logcat.txtto something like Pastebin, GDrive, Dropbox, Mega, or whatever you have access to