playbackTimeOffsetToAbsoluteTime

The offset between a playback time of the active source and its absolute representation. Adding this value to a playback time provided by the player (e.g. currentTime), will always result in an absolute timestamp.

Does not apply for playback times of ads.

When using a custom cast receiver, make sure to add startAbsoluteTime to the customData. As a reference, see Bitmovin's implementation here

Returns 0.0 if there is no active playback session.