This is purely an anecdotal story of stuff that happened to me. You may or may not find that interesting.
For quite some time my microphone for my computer has been an issue. There was always a background of static and interference so when I was raiding and using ventrilo (voice software) people found it somewhat difficult to hear me. A few weeks ago this suddenly became drastically worse for no particular reason, so much so that Gnome was complaining that when I talked he got a headache. The static background noise from my mic was really loud and annoying and I could not fathom why this would be.
We tried setting up my mic on Wendy's computer and it worked perfectly there, so clearly the mic was not at fault. I tried using both of our mics and trying them sitting on the table or with the headphones on and always the problem was the same. People told me is must be my sound card, which sounded a bit implausible to me but I certainly had no other explanation. Corporate Plunderer aka Snidely had a solution for me however; he had a spare mic that he was happy to ship to me to try to solve the problem. This mic connected through a USB too so it should avoid any possible issues with the regular audio in jack. I got the new mic, set it up and got people to hop onto ventrilo to test it... and still the exact same static issue.
What the *hell* is going on? New mic, new port, what could possibly explain this?
I decided that I should test my ventrilo settings to figure out if that could possibly be the issue. It seemed like a longshot since I sure didn't change my ventrilo settings a few weeks ago when the problem became dramatic, but I was running out of options. I checked every setting and nothing was wrong... and then I noticed that I had an option to change 'default sound input' to 'microsoft life cam'. Microsoft life cam is my webcam. This sits on top of my monitor directly beside my computer. It also happens to have (unknown to me) an audio input which is a tiny hole in the back of the camera - located almost directly beside my computer fan.
I unplugged the webcam and reconnected my new mic and lo and behold everything is perfect, crystal clear. Apparently I have been using my webcam for ventrilo input ever since I bought my new computer and I must have shifted my monitor slightly closer to my computer a few weeks ago which caused all the noise and stress. ARGH.
I could have noticed this forever ago if I had just unplugged my microphone and then tried to talk on ventrilo and it would have worked. Is it so terrible of me to not have tried talking on voice software with no mic active to see what would happen? It is a good thing for my computer that it is one of my truly beloved possessions or I might have to crack out the