Chosen Solution
I am getting told frequently from multiple callers that my voice is muffled or even non existent. I can not make any recordings on my device. I think there is an issue with my microphone.
If you are experiencing issues with the phone’s microphone, try using the solutions below to fix the problem. A common issue for this might be that the Mute button is on. Check that the microphone is not muted. Test the microphone by connecting a wired headphone that has a microphone. If the headphones work while connected, remove the headphones and continue onto troubleshooting the internal microphone. Test the audio by going to a quiet area and restarting the phone. Once restarted, record a new voice note by going to Messages and attaching a a recording to the message. You may also try and do a Skype Test Call. Skype is available from the Windows Store to download free of charge. Finally, the issue may be a simpler one. Check and see if the microphone’s opening is blocked. If so, use a dry cleaning cloth to wipe out any dirt or blockage. Again, if neither of the above works, you may simply need to replace the microphone.
A solution could be a quick observation of the casing grill, dirt filter and microphone. In my case, I cleaned the dirt filter, casing grill and even wiped the microphone but it did not help. I realized that the dirt filter was misaligned with the casing grill and therefore sound was blocked by this. I used a heating gun to soften the dirt filter and removed it, re-aligned it with the grill casing and ultimately the microphone. This fixed the whole voice muffled on caller’s end issue. (To breakdown this problem: Outer casing has to be clean. Dirt filter has a dedicated microphone hole that should be aligned to any hole on the outer casing. The microphone should fit on the dirt filter without any obstruction.) Hope this helps someone out.