Some of you may have heard of this software before. But, for those who haven't...
Here is a cross-platform voice chat client. It has a native linux client and works better than teamspeak and ventrilio IMHO.
Really nice audio setup wizard too; It should help for those that always have their mics either too low where you can't hear them or those that blow your eardrums out.
You can emerge it via portage
Package Names --
Client Name = mumble
Server Name = murmur
Website = http://mumble.sourceforge.net/
Some pretty nice skins for it as well. -- http://mumble-tower.de/downloads/mumble-skin
If you check the wiki, use the search function and google you can find the answer to most of your questions.
Remember to mark your thread [Solved] if your issue is fixed.