Yes I am streaming my teamspeak sound, gamesound and mic at the same time.
In the audio section, choose "Open audio mixer". Here you can add sources of streaming.
I have added "speakers audio" (that will record everything you hear in the speakers including teamspeak 3) and then "microfon". You need to add microfon if you want to be able to hear what you say on teamspeak otherwise you will just stream what all others are saying. Just remember that even if you have a push to talk button in teamspeak the stream will still stream all sounds they hear in your microphone so it's a good thing to tunr your microphone off from time to time.
Hope this helps.