A method for encoding audio objects as a data stream, comprising: receiving N audio objects, wherein N>1; calculating M downmix signals, wherein M≤N, by forming combinations of the N audio objects; calculating time-variable side information including parameters which allow reconstruction of a set of audio objects formed on the basis of the N audio objects from the M downmix signals; and including the M downmix signals and the side information in a data stream for transmittal to a decoder, wherein the data stream corresponds to a plurality of time frames, wherein the method further comprises including, in the data stream: a plurality of side information instances specifying respective desired reconstruction settings for reconstructing said set of audio objects formed on the basis of the N audio objects; and for each side information instance, transition data including two independently assignable portions which in combination define a point in time to begin a transition from a current reconstruction setting to the desired reconstruction setting specified by the side information instance, and a point in time to complete the transition, and wherein for each specific side information instance of the plurality of side information instances: the point in time defined by the transition data of the specific side information instance for beginning a transition corresponds to a first of the plurality of time frames, wherein the point in time defined by the transition data of the specific side information instance for completing a transition corresponds to a second of the plurality of time frames, the second time frame is either the same as the first time frame or subsequent to the first time frame. receiving N audio objects, wherein N>1; calculating M downmix signals, wherein M≤N, by forming combinations of the N audio objects; calculating time-variable side information including parameters which allow reconstruction of a set of audio objects formed on the basis of the N audio objects from the M downmix signals; and including the M downmix signals and the side information in a data stream for transmittal to a decoder, wherein the data stream corresponds to a plurality of time frames, wherein the method further comprises including, in the data stream: a plurality of side information instances specifying respective desired reconstruction settings for reconstructing said set of audio objects formed on the basis of the N audio objects; and for each side information instance, transition data including two independently assignable portions which in combination define a point in time to begin a transition from a current reconstruction setting to the desired reconstruction setting specified by the side information instance, and a point in time to complete the transition, and wherein for each specific side information instance of the plurality of side information instances: the point in time defined by the transition data of the specific side information instance for beginning a transition corresponds to a first of the plurality of time frames, wherein the point in time defined by the transition data of the specific side information instance for completing a transition corresponds to a second of the plurality of time frames, the second time frame is either the same as the first time frame or subsequent to the first time frame. a plurality of side information instances specifying respective desired reconstruction settings for reconstructing said set of audio objects formed on the basis of the N audio objects; and for each side information instance, transition data including two independently assignable portions which in combination define a point in time to begin a transition from a current reconstruction setting to the desired reconstruction setting specified by the side information instance, and a point in time to complete the transition, and wherein for each specific side information instance of the plurality of side information instances: the point in time defined by the transition data of the specific side information instance for beginning a transition corresponds to a first of the plurality of time frames, wherein the point in time defined by the transition data of the specific side information instance for completing a transition corresponds to a second of the plurality of time frames, the second time frame is either the same as the first time frame or subsequent to the first time frame. the point in time defined by the transition data of the specific side information instance for beginning a transition corresponds to a first of the plurality of time frames, wherein the point in time defined by the transition data of the specific side information instance for completing a transition corresponds to a second of the plurality of time frames, the second time frame is either the same as the first time frame or subsequent to the first time frame.