ne connection I’ve not encountered on a Blu-ray player before is a Zero Signal terminal. This phono doesn’t deliver any sound or vision, but connects to the Blu-ray player’s ground, or earth. The idea is to tether it to an unused phono input on your AV receiver (at last, something to do with those composite legacy inputs!) and thereby harmonise the GND reference level between the two devices. Apparently this is beneficial; while I couldn’t actually hear any difference, I took panacean pleasure from the process.