Dell Inspiron 5490 Microphone problem
Dell Inspiron 5490 having problems with its mic.

Video call and conferencing is one of the new standards may it be for meetings, webinars, conferences, work from home or home schooling.
With this webcams, mic and speakers which are used to be optional features now becomes very much needed part of work.

The problem comes when all of a sudden the mic of a Dell Inspiron 5490 is not working.

To narrow down on the cause and nature of the problem some troubleshooting is quickly done. But turns out a quick fix is not as expected and turns minutes to hours.... and in the end turns out to be half a day.

Some of the trouble shooting done and here are some of the symptoms
#1 Microphone is not detected, but the speakers are working.

#2 Using a USB headset, the headset microphone and headset speakers are working.

#3 Using an external webcam with integrated microphone works but this time using the webcam mic not the integrated one.

So narrowing it down, this thing has something to do with the internal microphone.

Checking the BIOS -> System Configuration -> Audio
Shows that the Audio is enabled, Speakers are enabled, Microphone is enabled.

First thought, hopefully this is not a hardware microphone problem.

First thing first, since much of it is working and this laptop microphone used to work... this should be caused by corrupted audio drivers or updated audio drivers that is not compatible with the unit itself.

Solution Attempt #1 - Do a windows update.
Results #1 - FAIL - mic still not working

Solution Attempt #2 - Do a Dell driver update.
Results #2 - FAIL - mic still not working

Solution Attempt #3 - Remove all audio drivers and have it re-detected.
Results #3 - FAIL - mic still not working, also speakers not working anymore. Needed to re-install the audio driver to have the speakers work.

Solution Attempt #4 - Download new audio drivers from Dell website.
Results #4 - FAIL - mic still not working, audio drivers now updated.

Solution Attempt #5 - Contact Dell support
Results #5 - DID NOT DO IT - maybe a little bit unhappy with some call center support that lets you wait for a long time.

Solution Attempt #6 - Access BIOS and disable audio
Results #6 - FAIL - mic still not working. Disabled audio, Disabled microphone, Disabled speaker. Doing this makes it worst, all audio is now not working. Well as expected since I disabled it then it should not work. This is in fact one of the dumbest troubleshooting. Of course by disabling it means it will not work.

Solution Attempt#7 - Access BIOS and enabled audio
Results #7 - SOLVED??? BIOS -> System Configuration -> Audio, Enable Audio, Enable Microphone, Enable Speakers. Speakers work and now the miracle, the microphone works. After a couple of hours of troubleshooting that focused more on the drivers, it turns out that a weird thing is really weird. Turning it off, turning it on - this change of settings for BIOS -> Audio solved the problem. SOLVED??? I can't explain why but all I can say is it solved the problem. This does not make sense. But it is a great feeling (partly) being able to solve the problem before the end of the day.

Dell Inspiron 5490 Microphone problem - solved by disabling and re-enabling it at BIOS.