[asterisk-bugs] [Asterisk 0011354]: Can not change Call-Waiting tone duration and frequency

[noreply at bugs.digium.com]

A NOTE has been added to this issue. 
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http://bugs.digium.com/view.php?id=11354 
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Reported By:                cahen
Assigned To:                
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Project:                    Asterisk
Issue ID:                   11354
Category:                   Channels/chan_zap
Reproducibility:            always
Severity:                   minor
Priority:                   normal
Status:                     confirmed
Asterisk Version:           1.4.15  
SVN Branch (only for SVN checkouts, not tarball releases): N/A  
SVN Revision (number only!):  
Disclaimer on File?:        N/A 
Request Review:              
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Date Submitted:             11-22-2007 20:09 CST
Last Modified:              04-02-2008 18:04 CDT
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Summary:                    Can not change Call-Waiting tone duration and
frequency
Description: 
Our users reports that the call-waiting tone on analog phones connected to
Zaptel hardware (TDM400 & TDM2400) is too disturbing.
I tryed to change it's duration in indications.conf AND in zonedata.c
(recompiled, etc...), but it doesn't change anything (changing other tones,
ie dialtone works fine!).
Basically, whatever is configured in those 2 files, the CWT is 300ms long
at 440Hz, and is repeated every 3 or 4 seconds! (it seems that a CWT is
emitted at the beginning of each ring-back tone sent to the caller)

Another issue is that when a call is bridged between 2 local extensions,
both parties hear the CWT, so no one knows who is concerned
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---------------------------------------------------------------------- 
 cahen - 04-02-08 18:04  
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Not at all... unfortunately this would have been too simple ;o)
callwaitingcallerid is disabled. If enabled, it is even worse.

The problem does not come from the tone's frequency, but from the
repetition of the CWT every 5 seconds and it's duration (300ms is too long
when repeated so often).
Their main problem is when their peer is dictating a telephone number or
email address, they can't head a digit (or character) because they hear the
CWT instead.

The solution would be to change the CWT in zaptel's zonedata.c, but i
can't figure where the ZT_TONE_CALLWAIT constant is being used (according
to my "grep -r", nowhere!)

As far as my knowledge of C leads me, i would guess that the solution
resides in asterisk's channels/chan_zap.c in the zt_callwait() function,
and found a quick and (very very very very) dirty hack to stop the CWT
after the first has been issued by setting a "static int" flag... but am
not sure at all that it is a safe solution. (if you really want, i can post
the patch, but the better would be i think to use ZT_TONE_CALLWAIT
instead...) 

Issue History 
Date Modified   Username       Field                    Change               
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04-02-08 18:04  cahen          Note Added: 0084968                          
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