did that aswell. this issue only started after the last update. was told to do a check on it from Samsung customer service. that work for a bit.
Test the receiver.
If you are currently on a call, the call will be ended when you test the receiver.
1. From the phone dialler, enter *#0283#.
2. Select RCV Packet Loopback ON (it may appear as either Start : RCV_1stMic or RCV_DualMic on some devices).
Say a few words as if you were on a call. If you hear your own voice, it's working correctly.