The present invention includes apparatuses and methods comprising a means for detecting the presence of speakers and microphones coupled to a portable multi-function device (such as Apple's iPhone™). In response, a portable multi-function device can adapt its output depending on the nature of the coupled headset device. In particular, a portable multi-function device containing the present invention can, upon detecting only one speaker in a coupled headset accessory device, combine the multiple channels of a stereo audio signal into a single mono audio signal. Likewise, a portable multi-function device containing the present invention can alert users to the absence of a coupled microphone.