Everything except the phone call works properly in my S9. If someone calls, I have to turn on the loudspeaker to hear the other person. I don't have to use the speaker for other applications like WhatsApp. Not sure what to do. Please advise
This is happening on my sons Note 9 too.
After running diagnostics on the phone which shows the mic to be good I'm thinking it's software based.
What he does at the moment is accept the call then switches to loudspeaker and then switches back to the mic by turning off loudspeaker.
Give it a try @MathewDN
If you can I'd also advise to send this as feedback via your Samsung Members App.
Current Phone ~Samsung Note 20 Ultra 5G SM-N9860_256Gb SnapDragon 865+ Samsung One Ui 3.0/ Android 11.