I use a Zoom H1n recorder on all my videos to record the audio, which I later add to the video Track. My problem is making the sync mark, I do a lot of Live Band recording and hand Claps, are not even visible with all the loud music on the waveform! I presently use a whistle, then find a quiet place and mark audio with that method, problem is that means going way out of the area, setting everything, and then fighting my way back to the front of the stages with all the equipment running, ..depending on the crowd that can be 10 minutes or more! I'm wondering if there is any way I don't know about, for marking the audio and staying up front where the action is occurring! Thanks John