By default, 'Skype' 'Ventrilo' 'TeamSpeak' 'Windows Messenger' and other 
"Voice over IP" programs or "Internet Chat" programs, automatically adjust 
the settings for your soundcard by selecting the Microphone input as the 
default recording device. Even if you select "Line In" the next time you 
reboot, these telephony programs will reset it to Mic. 

If you have used the Line In or CD Audio as your preferred recording source,
the next time you go to record audio you will find that your preferred source
has 'gone silent.' This is easily remedied. Simply go to your soundcard's
control panel or audio mixer and switch it back to your preferred recording
input (Line In, CD Audio, or whatever). 

Here's the step by step detail:
-  Programs > Accessories > Entertainment > Volume Control
-  From the Options tab Properties > Select Recording 
-  Under "show the following volume controls" make sure that Line In 
   is checked 
-  Click OK
-  Make sure that Line is Selected 

NOW:  
-  Programs > Accessories > Entertainment > Volume Control
-  From the Options tab Properties > Select Playback 
-  Under "show the following volume controls" make sure that Line In
   is checked 
-  Click OK
-  Make sure that Line In "Mute" is NOT checked

This can also be set from the Turtle Beach Mixer.

To manually enable the Microphone input when you want to use Skype, you can 
go into Skype > Tools > Options > Sound Devices and uncheck the box labeled 
"Let Skype adjust my sound device settings." You will still need to manually
re-enable your preferred recording input after you've exited Skype. 
'Skype' is only used as an example here. VTB does not endorse or reject any 
of these software.

WINDOWS VISTA:
   Start > Control Panel > Sound > Recording > Under Microphone select SRM 
   Device > Click on "Set Default". The rest of the devices will then display:
   "Unavailable".

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The voice in Ventrillo, Skype and other products that require mic input, is
set by the record source in the mixer and not the mic level in the playback
settings. It's easy to confuse the two mic settings. The one in the mixer only
determines what you hear, which is why you get speaker feedback when the mic
is not muted. 

If the record source is switched from mic to something else, then you can
still hear your voice from the playback mixer but the other side can't
hear you, which might be confusing since you can hear yourself perfectly.
Sometimes, programs that require the mic as an input might inadvertently
switch the record source from Mic to something else, and the mic stops 
working. But since you can still hear yourself in the headphones from the 
playback mixer, you think everything is OK and start scratching your head 
wondering what's wrong with the mic. 
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