[cisco-voip] Disconnect of the POTS connection to the CCME upon phone pick-up

[Petya Kohts]

Hello.

I'm experiencing problems with answering incoming calls
received to Cisco 1760 with VIC2-4FXO.

The error script is:
- someone calls to the office
- user picks up the phone (IP Phone 7905G)
- there's a little period of time (maybe half of a second)
when user hears the calling side
- IP phone goes on-hook (without user putting the receiver
to the base)
- calling side hears busy tone

I'm not sure but this may depend of ephone-hunt groups, because
if I pick-up the first phone in the hunt group then line disconnects
(almost always but not always), if I pick-up the second phone
in the hunt group the line stays (almost always but not always)!


Here is the output of "show voice trace" when picking up the 1st
phone in the hunt group:

2/1 State Transitions: timestamp (state, event) -> (state, event) ...
194615.790 (FXOLS_RINGING, E_DSP_SIG_0100) ->
194615.802 (FXOLS_WAIT_SETUP_ACK, E_HTSP_SETUP_ACK) ->
194615.806 (FXOLS_PROCEEDING, E_HTSP_PROCEEDING) ->
194615.838 (FXOLS_PROCEEDING, E_HTSP_ALERT) ->
194617.733 (FXOLS_PROCEEDING, E_HTSP_VOICE_CUT_THROUGH) ->
194617.737 (FXOLS_PROCEEDING, E_HTSP_CONNECT) ->
194618.029 (FXOLS_CONNECT, E_DSP_SIG_1100) ->
194618.382 (FXOLS_CONNECT, E_HTSP_EVENT_TIMER2) ->
194618.398 (FXOLS_POWER_DENIAL, E_HTSP_RELEASE_REQ) ->
194620.401 (FXOLS_GUARD_OUT, E_HTSP_EVENT_TIMER) ->
194620.401 (FXOLS_ONHOOK, E_DSP_SIG_0100) ->


Here is the output of "show voice trace" when picking up the 2nd
phone in the hunt group (talked 2 seconds):

2/1 State Transitions: timestamp (state, event) -> (state, event) ...
194799.130 (FXOLS_RINGING, E_DSP_SIG_0100) ->
194799.142 (FXOLS_WAIT_SETUP_ACK, E_HTSP_SETUP_ACK) ->
194799.146 (FXOLS_PROCEEDING, E_HTSP_PROCEEDING) ->
194799.182 (FXOLS_PROCEEDING, E_HTSP_ALERT) ->
194803.049 (FXOLS_PROCEEDING, E_DSP_SIG_0000) ->
194804.131 (FXOLS_PROCEEDING, E_DSP_SIG_0100) ->
194807.039 (FXOLS_PROCEEDING, E_HTSP_VOICE_CUT_THROUGH) ->
194807.047 (FXOLS_PROCEEDING, E_HTSP_CONNECT) ->
194811.138 (FXOLS_CONNECT, E_HTSP_RELEASE_REQ) ->
194813.137 (FXOLS_GUARD_OUT, E_HTSP_EVENT_TIMER) ->
194813.153 (FXOLS_ONHOOK, E_DSP_SIG_0100) ->


Another thing I'd like to specify: I had a talk with provider
day before yesterday and they admitted that they had changed
the configuration and there might be something wrong with
the new one. Since then they have been trying to figure out
what's wrong but there are no results still.


Can anyone give me some shortcut, some keywords to read about
or just explain me what's happening?


Regards,
Petya.