Chosen Solution

everything is super muffled, in-call and on recordings such as base camera app and snapchat. however, speakerphone works just fine.

Hi @pls_help , Use a bright light and a magnifying glass to check that the voice inlet hole at the bottom of the phone is not blocked with lint or dust. If it appears to be blocked DO NOT use a pin or probe to try and clear it as you might damage the microphone which is directly behind the hole. Try a vacuum cleaner, using short sharp bursts to see if this clears the obstruction. If it appears not to be blocked and since you state the it is fine when using the speakerphone then there may be a problem with the microphone itself.

This is an old post but I just fixed my LGG6 phone with this issue. It is most likely an app that is causing conflict with the microphone. I went into the Settings > Application manager> tap the three small dots at top right of screen> configure apps> App permissions> Microphone. Disable any app that you do not want to have microphone permissions. You can disable all that are active to see it it works then slowly add the ones you want to have active. It will warn you that it will cause the app to not function but it can be reenabled it you need too. This fixed my phone. Hope it helps.

Tried all not working for me on Samsung s6. I think something wrong with dual mic

You need to get an air in a can and blow out all openings possible in phone to clear it out, it worked like a charm for me on my Samsung Android.