Antwoord op "Why wont my microphone pick up any sound?"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.