A method for rendering an audio program to a number M of loudspeaker feed signals, wherein each loudspeaker feed signal corresponds to a reproduction speaker position within a reproduction environment, wherein M is greater than one, the method comprising: receiving the audio program, wherein the audio program includes one or more audio objects, and metadata associated with each of the one or more audio objects, and wherein the metadata associated with each object includes: position information indicating a time-varying position of the audio object within the reproduction environment; and a parameter indicating whether the audio object should be reproduced at the time-varying position indicated by the position information, or reproduced at one of N fixed positions within the reproduction environment, wherein N is greater than M; receiving reproduction environment data comprising an indication of the number M, and an indication of the reproduction speaker position within the reproduction environment to which each loudspeaker feed signal corresponds; determining, for each audio object, in response to the position information and the parameter associated with the audio object, a position within the reproduction environment at which to reproduce the audio object; and reproducing (670, 675) each audio object at the determined position by rendering the audio object into one or more of the M loudspeaker feed signals; wherein, when the parameter for an audio object indicates that the audio object should be reproduced at one of the N fixed positions within the reproduction environment, the determined position is the one of the N fixed positions that is nearest to the time-varying position indicated by the position information for the audio object. receiving the audio program, wherein the audio program includes one or more audio objects, and metadata associated with each of the one or more audio objects, and wherein the metadata associated with each object includes: position information indicating a time-varying position of the audio object within the reproduction environment; and a parameter indicating whether the audio object should be reproduced at the time-varying position indicated by the position information, or reproduced at one of N fixed positions within the reproduction environment, wherein N is greater than M; position information indicating a time-varying position of the audio object within the reproduction environment; and a parameter indicating whether the audio object should be reproduced at the time-varying position indicated by the position information, or reproduced at one of N fixed positions within the reproduction environment, wherein N is greater than M; receiving reproduction environment data comprising an indication of the number M, and an indication of the reproduction speaker position within the reproduction environment to which each loudspeaker feed signal corresponds; determining, for each audio object, in response to the position information and the parameter associated with the audio object, a position within the reproduction environment at which to reproduce the audio object; and reproducing (670, 675) each audio object at the determined position by rendering the audio object into one or more of the M loudspeaker feed signals; wherein, when the parameter for an audio object indicates that the audio object should be reproduced at one of the N fixed positions within the reproduction environment, the determined position is the one of the N fixed positions that is nearest to the time-varying position indicated by the position information for the audio object.