If you are using a BeoPort and LinkPlayer combination then can bypass any PUC.
You set-up the system so that [PC] activates the AV interface to the Apple, and you have LinkPlayer running so its menu then appears on your BV. All future commands are associated by the BV with the [PC] and most are forwarded to the LinkPlayer that then interprets them.
So for example I press [PC] and I get the LinkPlayer menu, I then use or [v] to scroll up and down the menu.
Pressing (GO) performs a selection, say "iTunes".
LinkPlayer then launches iTunes and passes commands to iTunes.
For example pressing the BLUE arrow => switches iTunes into using my playlists, and it starts playing the song from the previous playlist I used.
Press [MENU] is interpreted by LinkPlayer as a request to display the list of Playlists, which I can the scroll up and down (using and [v]) and I can then select a new playlist (GO) and a song from it ([v] and and (GO)).
I hope that gives you an example of the powerful ease of use that LinkPlayer coupled with a BeoPort can give you .....
edit: looks like my use of [ ^ ] to indicate the one of the scroll keys on the Beo4 is a forum BBcode for a birthday cake icon !!!!
First B&O (1976) was a Beogram 1500 ... latest (2011) change has been to couple the BL11 with the BL6Ks *sounds superb*