The solution - I has it.
mix tape is really a portable dj mixer on [technabob]
"On the surface, this shiny box looks like an old school cassette tape that’s been 24-karat gold plated. But take another look, and you’ll see that it’s actually a pocket-sized audio mixer for combining sounds from a pair of audio devices.
The Mix Tape Portable DJ Mixer lets you mash up tracks from any two iPods or other portable music devices. A pair of 3.5mm stereo inputs and a single stereo output let you gently fade between two sources just like a full-size DJ mixer.
There’s also a monitor jack that lets you cue up your tracks in the privacy of your own headphones. Just connect your media players, pop in a couple of AAA batteries, and you’ll be cranking out your own party mix in seconds.
The Mix Tape Portable DJ Mixer is available exclusively from Urban Outfitters website for $30 bucks."