Post edited 8:57 pm – August 31, 2011 by tweak

Generally when asking for help you should include as much information on your existing hardware and software setup, what fixes and tests you have tried, and any other details that maybe relevant to the issue.

[Edit: the sticky post at the top of the support forum explains this]

In your case, the first thing I would check is that your microphone is working by using a simple voice recording app.  All the major desktop distros should include a simple recording application.