I could also not find it, buth it is there - some where...
Relays
PGM168 + Flex button 1 to index 1 to 1
Enter type:
1 for LBC + extension number (Loud Bell Control)
2 for the Door box (press #*1 to open the door)
3 for external control relay No 1
4 for external control relay No.2
5 for external control relay No 3
So basically:
PGM168+flex button 1 ser to 3.
Enter for External All Call Page: 548
Enter for Internal ans External All Call Page: 549
Then after entering 548/549, the audio line comes "out" of the red phone plug at the MPB (processorboard), and the relay opens the speech connection.
So:
Audio connect amplifier to red phono plug.
Cut the phono cord and let it go through the relay.
(Green plastic screw connector marked Relay).
Then it works.
///doktor