I'm going back to the site on Tuesday.
I'll check then.
If I remember correctly, when I checked mmc 722,the 1st and 2nd keys were programmed as Call 1.
As I said before, the phone will ring, but when you pick it up,it continues to ring.
I tried pressing all the buttons, but each button would just beep.
I was unable to answer the call.
All functions of the 24D work properly when plugged into the same port.
Thanks again for all of your help.