Librem 14v1 wired microphone does not work

Here’s my output of cat /proc/asound/card*/codec* | grep Codec: Realtek ALC256.
I’ve googled a solution of modifying /etc/modprobe.d/alsa-base.conf to add options snd-hda-intel model=dell-headset-multi, but that did not work. Currently only the onboard mic works. What can I do to get my wired microphone to work?

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