A transport control, e.g., for use with an audio content playing device, the transport control for initiating play of dynamically rendered audio content selections that are rarely, if ever, played the same way twice is provided. The transport control includes a play indicator, e.g., a play button or the like, and a control indicator, for instance, a rotatable knob. The control indicator is linearly mapped to an interactive music engine having a plurality of component engines, each of which is controlled by the control indicator. Accordingly, the control indicator is referred to herein as a "multi-purpose" indicator. Upon altering this single multi-purpose control indicator, multiple components and music elements of the output can be affected. Thus, a transport control that permits a user to initiate play of dynamically rendered music selections with little input and/or decision-making is also provided.