Central telefonica Panasonic KX-T61610

Te paso los detalles. Pero segun lo que comentas no seria un problema de programacion, pareciendo mas a un problema de circuitos que se ponen a tierra al ingresar un llamado y por esto los corta.
Suerte
Move switch in cabinet to PROGRAM. Use station 10 phone to program
Code Description
00 Time/Date
01 System Speed Dial 00 to 99
02 System Speed Dialing ? Class Assignment
03 DSS Console Assignment
04 Dial Mode Tone/Pulse
05 System Switching Mode Automatic/Manual
06 System Switching Time
07 Outward Dialing Day
08 Outward Dialing Night
09 Ringing, Day
10 Ringing, Night
11 Toll Restriction Class Assignment
12 Toll Restriction, Deny Codes
13 Toll Restriction, Allow Codes
14 Host PBX Access Codes
15 Preferred Line Assignment
16 Programmable Call Waiting
17 Delayed Ringing
18 Delayed Ring Count
19 Intercom Alert Tone
20 Door Phone Ringing
21 Dial Call Pickup Group
22 Account Code Entry Mode
23 Call Duration Start Timer
24 SMDR Communication Parameters
25 System Data Dump
26 SMDR Incoming/Outgoing
27 Automatic Answer Mode
28 Hold Recall Time
29 External Pager Access Tone
30 Programmable Secret Speed Dials
31 Hook Flash Time
32 Disconnect time 1.5 Seconds or 4.0 Seconds
33 Calling Party Control
34 DSS Button Mode With/Without Transfer
35 DTMF Receiver Check
36 Transfer Recall Time
37 Parallel connection of a SLT with a Proprietary Telephone
38 F1/Save Changes the F1 key to a Save Key
39 F3/FWD Key Sets F1 to a FWD key
40 Executive Bust Override
41 Automatic CO Line Access, Outgoing
42 Programmable Call waiting Tone Type
43 Door Opener
45 Carrier Codes Assignment
99 System Data Clear