I develop a rate-distortion analysis of signaling games with imperfect common interest. Sender and receiver should be seen as jointly managing a communication channel with the objective of minimizing two independent distortion measures. I use this analysis to identify a problem with 'functional' theories of deception, and in particular Brian Skyrms's: there are perfectly cooperative, non-exploitative instances of channel management that come out as manipulative and deceptive according to those theories.