Understand that, just sorted my own muddle out.
I already "video in motion" set on. Honestly Occifer, I never ever use it.
The ones I am looking at have two outputs and two inputs.
The only "Y" I'll need will be on the Aux Out so that each could select it separately or together.
I understand that Aux Out will only replicate what the MMI is seeing from the TV unit. If the kids want a TV programme then I would have to select it for them on the MMI and then switch the MMI back to whatever I want on it (apart from a TV programme that is). Unless the TV tuner stops outputting when I switch to Radio, CD, AMI, Telephone or Sat Nav. Of course they would not be able to watch different programmes!!!
Proof will be when I glue it all together.
Just like you said, it is all as clear as mud.
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Ray at Wigan Pier
2014 A8L D4 4.0TFSI Gold (Sticker says "Beige") Can't leave you in a black smoke cloud anymore..
In progress, Nothing left to do.
Gone 2004 A8 D3 3.0 TDI. Ebony Pearl Black (with little bits of other colours and glitter)