Fixing no mic sound on a Dell Inspiron 1420 (or similar?)

Posted by james on Dec. 4, 2008

I had a friend call me today for a problem on their Dell Laptop. They were using Skype and could hear & talk fine using the laptop's built-in speakers and microphone, but for some reason when they plugged in a headset they could hear fine but the other party could not hear them. My first thought is that they're using a USB headset and Skype is not recognizing the second audio device, but they were using a normal non-USB audio headset.

So I poke around on their machine, and have her connect her headphones. The computer gives a (ginormous, ugly) popup for the sigmaltel sound control panel, showing the 2 (yes, 2) headphone jacks and the 1 mic jack. It shows that she has 1 headphone jack plugged in and 1 mic jack plugged in. But I still can't hear here on Skype. After playing around with Skype sound settings, I go back to the sigmatel control panel. I click on the microphone jack, and it gives options for "Line In" and "Mic". "Line In" is selected, so I select "Mic" and it works! The "mic" jack on the laptop comes configured by default to act as a "line in" jack, which is what you use to connect CD players and iPods into the laptop, but not microphones. It had to be manually switched to "Mic" to be compatible with the mic in the headset. It's not just a matter of levels; electret mics need a voltage supply to operate, so w/o the voltage you will get no signal at all.

So that's that. Dell is stupid (yet again), ships their laptop with a bad default setting (honestly, do they really think the line in is more used than the mic?). But more importantly, the sigmatel software is something no computer newbie would know to go poking around in. They should revamp the UI so you could see all the options avaiable to you w/o having to click on drop downs, and they really should offer a wizard. Without a wizard, most people aren't going to know what settings they need.