Metadata defining decoding and rendering instructions for media content to be co-rendered in a media presentation is divided and distributed as track fragments (15, 16) provided in different media container files (11). Track fragment adjustment information (20) is included in at least one such track fragment (15) in order to define rendering timing relationships between media content portions defined by the track fragments (15, 16) in a current media container file (11). The rendering timing relationships enable a correct time alignment of the playback of the media content to be co-rendered to achieve a synchronized media presentation. The track fragment adjustment information (20) is particularly advantageous in connection with tuning in or a random access in a stream of media container files (1, 11) comprising fragmented metadata.