And please note that you do not need an M patch box. It is a trivial piece of wiring together of DIN sockets in parallel. You would only need one connector to link two 5 pin (male) DIN plugs together and these 'joiners' (two 5 pin female sockets joined together in a single housing) are widely available, at least on line.

Just watch carefully which component you designate as the 'Controller' and which are non-Controllers. In theory you can just set each component to 'Auto' and let the links sort themselves out, but I have always found manual designations better (read your M user guides).

Cinema/Music: Trinnov Altitude32 8-16,218,Cloud 4 channel, Marantz UD5007,DSP5200SE(2+C),DSP3300(4),DSW(2),271,MShort Ceilings,AppleTV 4K
TV: Marantz SR7013 Wharfedale Diamond 9x4+Celestion(C)
Music: Roon,i7NUC8gen,QNAP TS253A, Sony Scala, MS200, Garrard DDQ650,Wharfedale Diamond 12.3
Kitchen: AD88 (bluetooth via i80).