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Continuous Tone on FXO

I'm trying to establish connection from my FXO on 2801 so that I can make external calls as well as calls to extensions in the company. When I dial an external number 9.......... my phone says connected and there is a continuous tone but no ringing. Likewise, if i try to call a number on my local PBX 4... it also says connected with a continuous tone and no ringing.

--- This is an extract of my config

voice-port 0/0/0
connection plar 4052 (This is the extension off the PBX which is connected to the FXO)
description *** connects analog line to fxo ***
caller-id enable
voice-port 0/0/1
dial-peer voice 4000 pots
description *** For Calls within the organization ***
destination-pattern 4...
incoming called-number .
port 0/0/0
dial-peer voice 1 pots
description *** used for external calling ***
destination-pattern 9[2-9].........
port 0/0/0
prefix 9

-CME1#show dial-peer voice summary
dial-peer hunt 0
             AD                                    PRE PASS                OUT
100    voip  up   up             3...               1  syst ipv4:
20001  pots  up   up             64046$             0                           50/0/1
20002  pots  up   up             64042$             0                           50/0/2
20003  pots  up   up             64041$             0                           50/0/3
4000   pots  up   up             4...               0                      up   0/0/0
1      pots  up   up   9         9[2-9].........    0                      up   0/0/0

-CME1#show voice port summary
                                          IN       OUT
============== == ============ ===== ==== ======== ======== ==
0/0/0          --  fxo-ls      up    dorm idle     on-hook  y
0/0/1          --  fxo-ls      up    dorm idle     on-hook  y
50/0/1         1      efxs     up    dorm on-hook  idle     y
50/0/2         1      efxs     up    dorm on-hook  idle     y
50/0/3         1      efxs     up    dorm on-hook  idle     y

=================        ==================

-CME1#show voice port 0/0/0

Foreign Exchange Office 0/0/0 Slot is 0, Sub-unit is 0, Port is 0
Type of VoicePort is FXO
Operation State is DORMANT
Administrative State is UP
The Last Interface Down Failure Cause is Administrative Shutdown
Description is *** connects analog line to fxo ***
Noise Regeneration is enabled
Non Linear Processing is enabled
Non Linear Mute is disabled
Non Linear Threshold is -21 dB
Music On Hold Threshold is Set to -38 dBm
In Gain is Set to 0 dB
Out Attenuation is Set to 3 dB
Echo Cancellation is enabled
Echo Cancellation NLP mute is disabled
Echo Cancellation NLP threshold is -21 dB
Echo Cancel Coverage is set to 64 ms
Echo Cancel worst case ERL is set to 6 dB
Playout-delay Mode is set to adaptive
Playout-delay Nominal is set to 60 ms
Playout-delay Maximum is set to 250 ms
Playout-delay Minimum mode is set to default, value 40 ms
Playout-delay Fax is set to 300 ms
Connection Mode is plar
Connection Number is 4052
Initial Time Out is set to 10 s
Interdigit Time Out is set to 10 s
Call Disconnect Time Out is set to 60 s
Ringing Time Out is set to 180 s
Wait Release Time Out is set to 30 s
Companding Type is u-law
Region Tone is set for US

Analog Info Follows:
Currently processing none
Maintenance Mode Set to None (not in mtc mode)
Number of signaling protocol errors are 0
Impedance is set to 600r Ohm
Station name None, Station number None

Caller ID Info Follows:
Caller ID is received after 1 ring(s)
Translation profile (Incoming):
Translation profile (Outgoing):

Voice card specific Info Follows:
Signal Type is loopStart
Battery-Reversal is enabled
Number Of Rings is set to 1
Supervisory Disconnect is signal
Answer Supervision is inactive
Hook Status is On Hook
Ring Detect Status is inactive
Ring Ground Status is inactive
Tip Ground Status is inactive
Dial Out Type is dtmf
Digit Duration Timing is set to 100 ms
InterDigit Duration Timing is set to 100 ms
Pulse Rate Timing is set to 10 pulses/second
InterDigit Pulse Duration Timing is set to 750 ms
Percent Break of Pulse is 60 percent
GuardOut timer is 2000 ms
Minimum ring duration timer is 125 ms
Hookflash-in Timing is set to 600 ms
Hookflash-out Timing is set to 400 ms
Supervisory Disconnect Timing (loopStart only) is set to 350 ms
OPX Ring Wait Timing is set to 6000 ms

All help appreciated

Everyone's tags (4)
Cisco Employee

Re: Continuous Tone on FXO


From the description, I didn't see the VoIP leg of the call or the call is from another POTS leg, the 2811 is a CME router?


please provide the detail call flow, also the following debug so that touble-shooting can be done,

debug voip ccapi inout

debug vpm signal


Cisco Employee

Re: Continuous Tone on FXO


Please provide a detail call flow.

And also in the config I see dial-peer 1 configured with prefix 9. I suppose the digit 9 is used as access code for external dialing.

So with "prefix 9" you are prefixing the digit 9 to the called number. Is the TELCO expecting the digit 9 as well?

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