A method and a computer program product for controlling a timing correlation establishing device to establish playback timing correlation between different contents to be playbacked are disclosed. The method includes displaying a main event block corresponding to a main video clip; displaying an auxiliary event block corresponding to an auxiliary video clip; displaying a time marker on a location of a first time point on a timeline according to an editor's manipulation to an input device; and when the time marker is positioned on the location of the first time point, if the editor perform a set of predetermined manipulations to the input device, utilizing a control circuit to establish a first trigger timing data for indicating that an auxiliary display device has to begin playbacking the auxiliary video clip when the main video clip playbacked by a main display device reaches the first time point.