Me again! I did some more investigation earlier.
Firstly, I looked through some of Peter Pan’s (very useful) diagrams in the Hifi4all forum. He shows the 1611 used to supply a stand-alone BL3500 several times. In none of these diagrams does he show that Aux Pin 2 to Pin 1 connection or anything similar. So unless we can think of a reason otherwise, let’s assume that connection should not normally be required!
Secondly, Peter Pan twice refers to selecting the input by pressing a Video Source (TV, DVD etc) and twice mentions using PC.
His diagrams are at the following links:
Second post here: https://www.hifi4all.dk/forum/forum_posts.asp?TID=23818&KW=1611&PN=0&TPN=55
3/4 way down this page (mentions selection with PC): https://www.hifi4all.dk/forum/forum_posts.asp?TID=23818&KW=1611&PN=0&TPN=57
Half way down this page: https://www.hifi4all.dk/forum/forum_posts.asp?TID=23818&KW=1611&PN=0&TPN=74
Half way down this page (again mentions selection with PC): https://www.hifi4all.dk/forum/forum_posts.asp?TID=23818&KW=1611&PN=0&TPN=79
I have tried selection using PC with my 1611 with no response; I think this may be a cut-and-paste error from his Beolink Active diagrams, which do indeed use PC to select.
Tonight as an experiment I tried connecting my 1611 by ML to my Beoport (Beolink PC) – the Beoport was set in Beolink Option 6. An iPad was supplying audio to the 1611’s AAL socket with a 7-pin DIN (with standard pins 2, 3 and 5 connected). I can activate this by pressing any video source on the Beo4 or on the Beoplayer screen and the sound appears from the Beoport’s speakers. So clearly the 1611 acts as a video-master when connected to a Beoport.
So I am still unclear as to what may force the 1611 to act as an audio-master. I might connect it by ML to a Passive (with IR eye) and some Passive speakers and see how that behaves (probably the same as the BL3500). I am a bit reluctant to try anything funny with the AAL data pins, but might take the risk!