Hi,I am trying to perform a simple operation but for some reason since I uninstalled my older version of audacity and replaced it with a new one I am not able to do it any more. I am just trying to record from the internet and I have done this before but now for some reason when I go to my control panel>Sound and try to enable stereo mix it is saying that it is currently unavailable. When I right click on it to enable it it only gives the disable option. I am sure it is a simple thing but I would appreciate some help. Thanks.
If it gives you the Disable option (only), it is simply because Stereo Mix is already enabled!
Have you tried recording what you are actually hearing through WASAPI?
On my system, only WASAPI will work to record live streaming audio. If you can hear something coming out of your speakers, WASAPI will record it. Make sure the right speakers are selected as output. I can output sound to external speakers or to the screen built-in speakers.
Hi, stereo mix seems to be enabled but comes up as currently unavailable in the recording section of the control panel, I managed to record some audio from the internet by setting wave as default but I do not know why stereo mix is unavailable, cheers.
I am sorry I do not know anything about WASAPI apart from the fact that it is extremely spicy and is eaten with sushi, can you tell me what this is, is this some sort of windows component already on the computer or is it separate? I dont know what Im doing. 
WASAPI is “Windows Audio Session API” (API = Application Programming Interface) - details from Microsoft here (but you don’t need 'em): http://msdn.microsoft.com/en-us/library/windows/desktop/dd371455(v=vs.85).aspx
It is an alternative audio “host” to the MME host that Audacity uses by default and the later “Windows Direct Sound”. The main reason that WASAPI is shipped with 2.0.5 is so that you can use “WASAPI loopback” to record audio that is playing on the computer (not all Windows systems can easily do this otherwise).
See this page in the manual: Audacity Manual
WC