[Asterisk-bugs] [Asterisk 0009660]: Asterisk can't establish dialtone after brief hangup

[noreply at bugs.digium.com]

A NOTE has been added to this issue. 
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http://bugs.digium.com/view.php?id=9660 
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Reported By:                mmacvicar
Assigned To:                
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Project:                    Asterisk
Issue ID:                   9660
Category:                   Core/General
Reproducibility:            always
Severity:                   minor
Priority:                   normal
Status:                     new
Asterisk Version:           1.4.4 
SVN Branch (only for SVN checkouts, not tarball releases): N/A  
SVN Revision (number only!):  
Disclaimer on File?:        No 
Request Review:              
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Date Submitted:             05-03-2007 14:08 CDT
Last Modified:              07-06-2007 16:38 CDT
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Summary:                    Asterisk can't establish dialtone after brief hangup
Description: 
Asterisk can't establish dialtone after brief hangup

When I press the hook-switch (i.e., receiver button) and then let go to
make a new call, the phone doesn't establish dialtone unless I hold it down
for for 4-5 seconds.

Reproducible Steps:
1. Pick up handset and establish dialtone.
2. Press the hook-switch for 1-3 seconds and let go

After letting go of the hookswitch, the sound on the line is silent for a
moment then a computerized squeal is heard briefly and silence continues.
The asterisk console displays the following messages when "core set verbose
10":
--------------------
    -- Starting simple switch on 'Zap/7-1'
    -- Hungup 'Zap/7-1'
[May  3 11:31:45] WARNING[2241]: chan_zap.c:1616 zt_set_hook: zt hook
failed: Device or resource busy
--------------------

We are using analog Astra Telecom 480e phones connected through internal
wiring to TDM400P cards in our asterisk server.


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---------------------------------------------------------------------- 
 jmhunter - 07-06-07 16:38  
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Same here.

I'm using a TDM400P with Asterisk 1.4.4.
Zaptel is either 1.4.1 or 1.4.2 (I have both sets of source code around -
how can I tell which is running?)

If I pick up the telephone handset, and then hang up & pick the handset up
again too quickly, I get the following:

    -- Starting simple switch on 'Zap/3-1'
    -- Hungup 'Zap/3-1'
[Jul  6 22:47:02] WARNING[5398]: chan_zap.c:1616 zt_set_hook: zt hook
failed: Device or resource busy
[Jul  6 22:47:05] WARNING[5398]: chan_zap.c:6897 do_monitor: Read failed
with -1: Unknown error 500

If I listen straight after picking the handset up again, there are a few
seconds of silence and then a 1-second noise I can best describe as similar
to a modem trying to train with the other end. At that point it goes silent
again, and next time I hang up / pick up it is fine.

Other info of note:

I am using 'UK' tones/zones with my Asterisk setup. Not sure if that
affects anything?

I have experimented with the following in zapata.conf (in a failed bid to
reduce the time Asterisk needs to differentiate between a hookflash and
hangup - the UK standard timings for these are considerably shorter than
the USA ones) but this hasn't helped:

debounce=300
flash=200
rxflash=200

(If there is a guide to what these timings actually mean, I'd appreciate
being pointed in the right direction - I wasn't sure which settings to
actually set in order to achieve my goal.) 

Issue History 
Date Modified   Username       Field                    Change               
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07-06-07 16:38  jmhunter       Note Added: 0066632                          
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