This paper describes a study in which several musicians were invited to jam with an “AI agent”. Behind the scenes, the agent was actually a human keyboard player. In interviews about the experience, the musicians revealed that they had taken a different attitude to musical interaction than they normally do with human musicians. They had lower expectations to the musicality of the system, and therefore felt less constrained by musical rules. A perceived freedom from judgement allowed some of the musicians to feel less self-conscious about their own performance.