Hello, I have Acer Aspire A515-56-57XR with alc255 and have similar issue, managed to solve it for now with at a cost of losing functionality of internal microphone.
My issue was the headphones/micophone always appeared plugged in and even after actually plugging it in had to manually switch it, also the earphone microphone didn't work at all. After months someone sent me a fix on acer community forums. I will send that fix here and hope it works for you. This fix will cause internal digital microphone to stop showing completely. Add these to end of /etc/modprobe.d/alsa-base.conf # Headset mic fix options snd-hda-intel dmic_detect=0 options snd-hda-intel model=alc255-acer After, reboot when you plug in the earphone/headphone a pop up will show choose anything, now your external microphone should start working. Also, when you unplug earphone/headphone it should automatically switch to internal and hide external ones as well. The pop up will show up every time you plug in to fix this use gnome extension called Remove Audio Device Selection Dialog. -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1918142 Title: Headphone microphone doesn't work - ALC255 To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1918142/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs