most common problem is the mic jack that breaks. causing the internal mic not working.
There IS a fix, but the previous post deleted the image.
edit:
I fixed the mic problem, permanently.
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Blurry.
Basically, I just solder the lower and upper pin together.
Originally, when you insert an external headset /w mic, pin pin switch breaks, and you cant use the internal mic. But over time, even when you dont use a headset, the pin switch break itself. You can fix this by cleaning the pin, pull the pin upwards, or just solder the damn thing.
I'm not even gonna use a headset to play games.