Individual audio tracks (20-24) for interactive reproduction at a remote toy (104) are each encoded with a sub-audible tone (12-18) or code that uniquely identifies the track with audible output and/or functional operation of the toy (104). Detection of the sub-audible tone at the interactive toy opens the audio path and permits related motor control in the toy, whereas absence of a relevant sub-audible tone disables at least the audio and, preferably, both the toy's speaker (122) and at least one controllable motor (130, 132). The sub-audible tone (12-18) or code is inserted for the duration of activity only and may come into and out of existence as a specific character track (amongst the plurality of individual audio tracks) moves between active and inactive phases. The audio tracks for remote transmission at the toys (104) are assigned to only a first channel of a stereo audio circuit, with a second channel of the stereo circuit assigned to support a context or background track that is produced from speakers (51) of a media player (54) physically separate from the remote toys (104). Conventional synchronized transmission of both stereo channels provides a basis for interaction, with synchronicity between the media player (54) and the remote toy (104) maintained by the sub-audible tones (12-18). For simultaneous audio activity in multiple toys, a different sub-audible tone is used relative to individual tones or codes used to control audio output and operation of those multiple toys.