I am using an iPad air with DJay 2 + Spotify. Can I use any 3.5mm splitter or am I required to use the Griffin DJ splitter cable in order to successfully queue music?
Yes, it’s a special adapter for split output. Standard don’t really split the channels per se or at least not in the manner required.
It’s very easy to create one yourself, go get one male jack and two female jacks. From the male jack connect the right channel to one female jack and connect the left channel to the other female jack and voila done. Costs about less than 5€