On this model, the indicator of micphone mute is not working properly in Linux due to how the device is implemented in ALSA and pulseuaio. The microphone device is suplex and has its micrphone LED event set to the wrong one.
Use the following script to fix this:
#!/bin/bash
echo -n 7 > /sys/class/sound/card1/controlC1/led-mic/detach
To run this at startup, use a systemd unit similiar to this:
[Unit]
Description=Fix ThinkPad T14s AMD Microphone Led
[Service]
ExecStart=/usr/bin/fix-tp-mic-led.sh
[Install]
WantedBy=multi-user.target
The microphone mute LED only tracks the status of internal microphone. More testing is needed to determine correct behavior under Windows and mimic it back in Linux.
Thanks for this. I started collecting workarounds for the P14s in https://aur.archlinux.org/packages/thinkpad-p14s.