02-26-2019 05:42 PM
Lenovo X1 Yoga Gen 1 with Windows 10
FnLk is enabled (and can be enabled/disabled through Fn and Esc key)
Fn+F1 turns speaker on/off and LED lit properly
Fn+F2 reduces volume properly
Fn+F3 increases volume properly
Fn+F4 mute/unmute of microphone no longer works, and LED stays off
Fn+F5 reduces screen brightness properly
Fn+F6 increases screen brightness properly
As shown above, most Fn+F(x) function keys work just fine.
Fn+F4 worked fine until about a week ago (when it was last used).
How can Fn+F4 be made to work properly again?
Solved! Go to Solution.
02-27-2019 08:58 AM
Fn+F7 to Fn+F12 all work correctly.
The problem is solely with the combination of Fn+F4 to turn on/off the built in microphone.
Note, the F4 key itself works fine, eg. on its own, or eg. in combination with the Alt key.
02-27-2019 10:48 AM
I just ran Lenovo "System Update" and the following three updates have been installed.
After these installs completed, the Fn+F4 is working again.
It appears that the updated ThinkPad Hotkey Features Integration Package may have done the trick.
To answer your question:
I'm now able to use the mute function in the Recording tab of the Sounds control panel,
yet that shouldn't be a surprise, given that Fn+F4 works again too.
I can't answer what it may have done while in the failure mode.
03-20-2019 01:30 PM
Looks like another Windows 10 update made the original problem reappear.
Some updates were installed a few days ago, and next day or so I noticed the problem is back.
As previously stated in the original post, the problem is solely with the combination of Fn+F4 to mute/unmute the microphone.
All other combinations of Fn with F1-F3 and F5-F12 appear to work fine.
Per your prior question I've now tried to mute and unmute the microphone in the Recording tab of the Sounds control panel.
This works fine, including to turn the LED in the F4 key on and off appropriately, as well as to show the appropriate black symbol on the screen.
03-20-2019 04:20 PM - edited 03-20-2019 04:21 PM
I have never heard a problem like this before, where pressing mute button in Sound properties works, but Fn-F4 doesn't work. Is there any possibility that the F4 key is intermittently broken? For example, can you use Alt+F4 (with FnLock turned off) to close a window?
EDIT: never mind, I saw where you confirmed the F4 key by itself works OK, in a previous message