I am facing a similar issue. Initially the speaker would work fine - now when I am on a call - the speaker goes off while the phone is still in the speaker mode ! ... It's a bug / issue with the hardware it seems !
My wife's Note 9 did the same thing or similar issue in the middle of her call. She had several other calls and responded to them, but they could not hear her.
I also called my phone (Note 9 as well) and the issue persisted. I could hear her when she switched to speak, but as far as the mic, it wasn't working.
I called Tech Support... Did everything in their power to no avail, then contacted Customer Care... I told them we had only had the phone for less than three weeks and we didn't want to use the warranty nor did we want a refurbished phone.
They sent us to one of their (Verizon's) Corporate Locations to address the situation. I swapped it out with a NEW NOTE 9 - same color. Now We are happy campers, but still concerned it may do this again.
So did anyone get help seems Samsung letting a bunch of issues go on un helped ??. My phone has this issue and the volume randomly going up and down wile I listen to music or on YouTube????? Come on Samsung help us out
i also have same issue started yesterday as on : 25 - sep - 2018 during call its auto go to speak even speaker icons is off , i have to turn on and then off ... not good if you have important call every one can hear this tooooooo bad
ok i called samsung here they ask me to do ...
go to setting app and then click 3 dots on top right and click "reset app preferences" and then go to setting general management and then reset and then reset.
seems to me working..
asking quesition to all those have this issue do you have these apps in your device.
.1 BIGO LIVE
.2 fortnite game
i have doubt on these apps.