Summary:ASTERISK-04793: robotic audio in sip and voicemail + dbl speed vm
Reporter:Joe Antkowiak (antkojm1)Labels:
Date Opened:2005-08-08 00:24:25Date Closed:2011-06-07 14:03:19
Versions:Frequency of
Environment:Attachments:( 0) 4918-siprobot-debugs.txt
( 1) 4918-voicemail-debug.txt
( 2) speedy-voicemail.WAV
Description:I have a really really strange issue.  Whenever calls come in to a cisco sip gateway through a pri, when the calls connect the audio heard on the pri channel is very distorted and sounds robotic.  I initially thought this was an issue on the cisco sip gateway until two things happened.  One, I was having the same thing happen, in addition to double-speed recording and playback, in voicemail, even on calls that are cisco 7960>sip>*>iax>* Voicemail.  Two, I'm having the issue on calls now even when the cisco sip gateways aren't in the call path.

*does not* have issue
PRI>Cisco IOS>SIP>*>Cisco 7960
Cisco 7960>SIP>* Voicemail

*has issue*
PRI>Cisco IOS>SIP>*>IAX>*>SIP>Cisco 7960
PRI>Cisco IOS>SIP>*>IAX>* Voicemail
PRI>Cisco IOS>SIP>* Voicemail
Cisco 7960>SIP>*>IAX>*>SIP>Cisco 7960
Cisco 7960>SIP>*>IAX>* Voicemail

Codecs tried: ulaw, g726
voicemail file formats tried: wav, wav49, gsm

I used up some paid support with digium trying to figure this out.  They suggested I try removing the zaptel cards from the boxes involved to see if its timing related, and I did that (they weren't needed anymore anyway), and we still saw the same issue.

Any ideas?  What kind of information do I need to provide here?
Comments:By: Mark Spencer (markster) 2005-08-08 02:27:30

This is almost certainly a mismatch in the sampling sizes (i.e. your cisco gateway is set to 40ms packets instead of 20ms packets or something similar).  If you have an open tech support ticket with Digium, do not open the issue here.  If you have not had a satisfactory completion of your ticket with Digium, e-mail me your ticket number off of the bug tracker markster@digium.com.