[off topic]
Yes they use forms. Every big solution center uses forms. In fact, we ask 'standard' questions at first on these forums too, that is how problem solving works, everywhere... It is by properly answering these 'standard' questions that the people can help you further and pinpoint the problem so that they can escalate the issue and forward you to the correct people if the standard solutions don't work.
If you haven't seen that happening than you either haven't spend much time on the Windows Live Solution Center forums, or you haven't properly answered the questions they've asked. Also remember that they need to answer thousands of questions, so it can take a few days.
Thus to solve your microphone problem you far better go to the Solution Center than hoping someone here comes with a solution as this is a very vague issue.
Other than the common "
reinstall wlm and/or the sound drivers"-response there is mostlikely nobody here who would be able to help you with this.
[/off topic]
So...
Have you tried reinstalling Messenger?
Have you tried reinstalling and even upgrading the sound drivers?
Other than that I'm afraid we can not help you with this and you might be better of contacting Support on the Windows Live Solution Center forums.
And if a solution is found, please let us know.