I am using Nokia 6 and facing an issue that volume of popup [USSD messages] which will come on disconnecting the call. the notification sound is too much annoying. It is so loud, seems to pears into the ears.
I had been suggested to do the following steps with no results. From online chats.
Step 1) Dial star hash star hash 372733 hash star hash star
Step 2) Now perform Speaker Test
During speaker test L. Speaker had less volume than right speaker [don’t know whether this is set as such. But still the popup sound was coming from the ear piece.
Step 3) Perform Force Restart To force restart device by pressing volume up key and power key button for 20 sec then device will and device automatically restart.
Step 4) Try to perform Factory data reset after taking proper backup.
For the three tests conducted the notification sound had been the same
May be the notification sound must come from the speaker located near mouth piece or it must be adjustable or even be mutable