If, like me, you have an older AV processor that does all the hi-res audio decoding you need, but whose HDMI isn't with the times anymore (new TV, PlayStation5 and an Apple TV) than this unit is an ideal HDMI switch with pass through audio extractor. The alternative is ARC or eARC but that doesn't allow for passthrough hi-res audio.
The only drawback of this SW411 (and I guess every HDMI audio extractor) is that lip-sync (synchronisation between the TV and the audio) needs to be manually applied since the AV processor doesn't get video data with this audio only HDMI connection. But lip-sync can be applied either in the AV processor, or in the media player.