Can you please tell me if the Nexus 7 supports the use of a headphone/mic combo so that when the audio jack is inserted the internal mic is bypassed and the external mic provides the source of audio. In other words does it work the way any ordinary cell phone does? I ask because I have received 2 units and neither works in this way (the internal mic continues to be used when I insert a plug that includes a mic). Google seems to think they muct be defective (e.g., a solder joint is bad) but given that you have taken the tablet apart, I thought you could provide a definitive answer.