Updated to WP8.1 couple months ago and everything was working fine.
Now handset speaker/mic doesn't work. Phone does work with headset plugged in or connected to my car via Bluetooth.
Volume control drop down scroll bar only shows headset volume (used to show ringer volume as well). Ringer does work.
Tried shutdown/restart, hard reset, and now have done a full reboot back to initial state. No change.
You have already done quite a bit to try to resolve this, JimLarsen!
At this point, we would need to check into your warranty replacement options. Is there any damage to the Lumia 928? Has it been exposed to any water/moisture that may affect the function?
If not and if you have had the device less than 12 months, you may qualify for the replacement.
I will send a direct message to get more information from you.
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