This article handles the occurrence of the ‘microphone gaffe’ in the context of sports broadcast speech. This specific communicative event is featured by the public mediation of live speech to media audiences, wilst the speakers are unaware of their on air-status. Taking on a general pragmatic viewpoint, this article examines the microphone gaffe in terms of its specific participation framework and debates its humorous possibilities. It is claimed that the core element underpinning these communicative situations comprises the brief non-recognition of the media audiences by the speakers. The audience, repositioned as non-participants, effectively find themselves in the role of the ‘eavesdropper’ on a private conversation. On the production side of the communicative scheme, the incorrect conviction of savoring this brief ‘private’ speech event is attended by a shift of footing, where the commentators’ institutional identities become resored with their non-public personas, proven by kinds of backstage talk that opposes their frontstage performance. This article asserts that in case of microphone gaffes, humorous effect emerges from the diverse absurditities between the actual and the supposed footings, as well as from the ensuing recontextualizations that insert the primary communicative act within a supplementary communicative level. The aim of the article is to suggest and develop a general theoretical framework for the analysis of unintended humour in media discourse.