through this section you can setup up to 4 external audio sources that we call EXT1-EXT2-EXT3-EXT4 corresponding to audio input lines of your soundcards. For each external source you can setup:

Audio Card
Here you can choose the desired audio card to capture the sound. The "exclusive mode" flag will enable the use of sound card only for MB STUDIO for best audio quality.

Name
Here you can write a more friendly name for display the source name.

Level
Here you can set the volume of the capture (this control could not work with any sound card, if it's the case, use the audio control panel of your sond card to set the desired volume)

Properties
this button allow you to setup additional properties to use when the EXT is aired. This is a global setting, but you can customize the properties on any item in playlist, minilist or break.

Prelisten
this button allow you to prelisten the audio from this source. You should setup a Prelisten Audio Card in Setup\Audio\Options prior to use this button.