Sony SPP-A972 - Manual (Page 45)

Telephone Features
45 US
Telephone Features
continued
Receiving a call while talking
If another call comes in while talking, the LINE 1 or LINE 2 button on
which another call is coming will flash.
1
Press (HOLD).
The line in use is put on hold.
2
Press (LINE 1) or (LINE 2), on which another call is coming.
3
Press (CONF) (conference).
Now you can talk to both parties. (Three-way conference)
Note
If you do not press (HOLD) in step 1, the first line will be disconnected.
To disconnect the lines during a three-way conference
To disconnect both lines at the same time, press (OFF).
To disconnect line 1 and talk on line 2 only:
Press (LINE 2).
To disconnect line 2 and talk on line 1 only:
Press (LINE 1).
To put the lines on hold during a three-way conference
Press (HOLD). Both lines are put on hold.
To resume the conversations on both lines:
Press (CONF).
To resume the conversation only on one line:
Press (LINE 1) or (LINE 2), for the line you want. (The other line is kept
on hold.)
Tip
During a three-way conference, you cannot use “call waiting” service even if
you press (FLASH/CALL WAITING) or (FLASH).