[ddouglass]

Actually you don't have a preview "screen" but instead it allows you to preview the audio to make sure it is the correct version. There are some songs that are crossovers from country to pop or pop to country. They are not the same though they have the same title.
Yes headphones would be the option to use this so it doesn't interfere with current singer.
Most computers have one built-in audio card and will accept a second one easy enough. I use my added card as my primary because it is better, but can use the built-in card for the search preview.