[Guy]

matador wrote:

Bonus question: when is the Masterlink socket used in these boxes, seem like every time somebody want to use them the answer is “find yourself a fully wired PL cable”.

I didn’t answer this bit above.

The ML socket is used when the Passive is used in a link room as part of an ML system. The only input (data and audio) will be the ML socket, and the output (to passive speakers) will be controlled by connected IR eye.

Conversely, if the only input to the passive is via PL, then it is just acting as a dumb amplifier and no control is required (or indeed possible).

So you can connect either ML and IR eye, or just PL.