Internal microphone doesn't work when using headphones

Ubuntu 19.10 (Eoan Ermine)

When not plugging in anything, my internal input and outputs work perfectly. When I plug in my headphones, which do not have microphone but only speakers, my input devices look like this (using pulseaudio volume control):

• Internal Microphone (unplugged)
• Microphone (plugged in)

Before plugging in my headphones, my input devices look like this:

• Internal Microphone
• Microphone (unplugged)

Now I think ubuntu thinks my headphones contain a microphone, but they don't. Selecting the Internal Microphone does not give any sound, because it says they are unplugged.

I got my headphones and internal speakers to work yesterday by pure luck, but now plugging it out and in again doesn't fix anything. I've also tried rebooting several times and muting one channel of both microphones.

If you need any other information, I'll be happy to include it!

EDIT:

It works sometimes, which is very weird. I have no idea how to consistently get it to work. Sometimes it will not work after rebooting a lot of times and booting with headset plugged in or not. And sometimes it just works for no reason.

sudo apt install alsa-tools-gui

hdajackretask

Select the appropriate sound card up top in Select a codec:

Then make the Black Mic (headphone jack) override Not connected

Lower right corner, select Install boot override

Then reboot and test

Known bug since 2012. https://bugs.launchpad.net/ubuntu/+source/pulseaudio/+bug/1025388

If you'd like, you can add yourself there to the number of users affected.