This seems to happen with a variety of our laptops, so we are certain it is not the HDMI ports, the cables have indeed also been replaced as a double check, it feels more a software issue, the display never has an issue, as in it stays on, no cut outs nothing, it is purely the audio side, where of course it will be jumping as the computer switches rapidly between Speakers and the HDMI output, almost as if it is detecting it over and over.