[asterisk-bugs] [Asterisk 0009660]: [patch]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:                   Channels/chan_zap
Reproducibility:            always
Severity:                   minor
Priority:                   normal
Status:                     ready for testing
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:              11-05-2007 16:39 CST
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Summary:                    [patch]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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Relationships       ID      Summary
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related to          0010360 E&M Wink trucks no longer interpret...
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---------------------------------------------------------------------- 
 jmhunter - 11-05-07 16:39  
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meneault - thank you for your advice.

I have decreased the rxflash time (although this was not the issue - I
waited for the console to show "Hungup 'Zap/3-1' before picking up the
handset again), and this works as described.

The big change, though, came when I switched from fxs_ks to fxs_ls
signalling. This has completely eliminated the buggy behaviour.

To a lay person, what is the difference between Kewlstart and Loopstart?
Why would somebody choose one over the other? I seem to remember the
documentation recommends Kewlstart.

I will try your patch now and let you know if it works as well. 

Issue History 
Date Modified   Username       Field                    Change               
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11-05-07 16:39  jmhunter       Note Added: 0073160                          
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