I am running Ubuntu 12.04 on a HP Pavilion dv6 laptop. My laptop's mic is detected, but does not pick up any sound. When I mute and then unmute it, a faint pop can be recorded by it, but the mic then gets no more info. I have set my audio profile in PulseAudio Volume Control (pavucontrol) to Analog Stereo Duplex. I have tested and confirmed that the external mic port can record sound using my headphones as a microphone.
I found out that my mic is broken, there is not an Ubuntu problem. Thanks for the help.