Systems and methods selectively mix a first and second song together during a live performance. The first song has a plurality of first stems, each having stereo audio that combine to form the audio of the first song. The second song has a plurality of second stems, each having stereo audio that combine to form the audio of the second song. A computer, with memory and a processor, executes machine readable instructions of a multiple channel audio mixing application with stored within the memory. The multiple channel audio mixing application plays and mixes audio of at least one of the first stems with audio of at least one of the second stems. The multiple channel audio mixing application is controlled in real-time during the performance to select the at least one first stem and the at least one second stem for the mixing.