You would need a dual output sound card, preferably made for DJ-ing. In some cases they will have the option to use one of the two outputs through a headphone jack. The Reloop Play DJ is an example.
However, at the end of the day you will be better off with a Pro with built-in soundcard imho. Less things to hook up for example.
And LE versions of software are basically not worth very much, i.e. upgrading from LE is almost as expensive as buying new. So you will get the Serato software which you’ll ignore and just buy a VDJ license.
A Mixtrack here is 199 euro, the sound card 99. Grand total is 298 euro. A Mixtrack Pro is 213. Total savings 85 euro, more than enough to cover the price difference of not having the VDJ LE to upgrade I think.
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