Developers, please note: sometimes this happens, and the volume tab cannot be opened (no arrow on right), fixed by a restart and before this, sometimes, the audio can stop working completely.
MarcinP replied at 2017-5-29 03:57
Hi
Go to file manager - internal storage - downloade - cut file and past directly to internal mem ...
I did that but it did not work, however I finally received the OTA update today and the update went fine. I can even use Google assistant now and slide down the notification bar even from the middle of the screen. By the way, formatting and resetting a phone should NOT be a solution for a minor problem like not receiving a minor update, as it is quite cumbersome to retrieve all the backup data again after factory reset.
Since the March update VoLTE no longer works in the network of o2 / Telefonica Germany. I have also the V3.02_20170411 with SPFT re-installed and tried - VoLTE does not work for outgoing calls.
So I am now again switched to V3.02_20170225 ROM, so it works great again.
Please correct this error.