VLC - no sound during web-cam video capture

[kitpgm]

Hi I tried to use VLC player to record a video. But it did not record sound. I couldn't hear any sound during video capture or during playback of the recorded file. I used the "Open Capture Device" option in Media menu. Capture mode was Video 4 Linux 2. For the audio device name, I tried many options:
1) alsa://
2) alsa://hw:0,0
3) alsa://plughw
4) alsa://plughw:Intel
Vlc did not display any error during capture. But still I could not hear any sound. Please, can somebody help me? (I have Linux Mint 12 with built-in web-cam in my laptop. In System settings, my built-in microphone was not muted. vlc-plugin-pulse is installed.)