For a fix that worked for me, see https://askubuntu.com/questions/1218136/internal-microphone-doesnt-work-when-using-headphones/1285982#1285982.
The fix:
1. Run
sudo apt install alsa-tools-gui
hdajackretask
2. Select the appropriate sound card up top in Select a codec.
3. Then make the Black Mic (headphone jack) override Not connected.
4. Lower right corner, select Install boot override.
5. Then reboot and test.
For a fix that worked for me, see https:/ /askubuntu. com/questions/ 1218136/ internal- microphone- doesnt- work-when- using-headphone s/1285982# 1285982.
The fix:
1. Run
sudo apt install alsa-tools-gui
hdajackretask
2. Select the appropriate sound card up top in Select a codec.
3. Then make the Black Mic (headphone jack) override Not connected.
4. Lower right corner, select Install boot override.
5. Then reboot and test.