my video export to MPEG4 no longer follows Start & End markers!? it does the whole length if any thing is on the tracks past the end marker. the only things I did recently is disable the ads and increased the buffer due to the can't open waveform errors.
@nhong-xiong The area between the End & Start is called the Range, tick this box in the export window to export only the objects within the Range, if this box is unticked it will export the entire timeline.