dodgy line in cable and separating elements of a track

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so ive got a dodgy headphone jack on my laptop, and the connection is obviously loose so somtimes the line in cable isnt quite in properly.

normally when this happens you just get buzzing/feedback, but sometimes if you do it just right, it only plays certain elements of the track (e.g. the guitars but no drums)

so does it not follow that in this case there must surely be some way to achieve this effect using software, in order to extract for example just the guitars of a track...

any ideas how I might go about doing this??