[asterisk-users] TDM400P periodic sound clicks on FXS

[Matthew Fredrickson]

Costa Tsaousis wrote:
> Matthew Fredrickson wrote:
>> Costa Tsaousis wrote:
>>  
>>> Hi,
>>>
>>> I am having periodic sound clicks (2-3 per second) on all FXS of a 
>>> TDM400P when the remote end is my VoIP provider. However:
>>>
>>> - recording the conversation on the asterisk, does not have the 
>>> glitches, although I can hear them on a real phone.
>>> - My VoIP provider to my VoIP phones through the same asterisk is OK.
>>> - TDM to TDM through the same asterisk is OK.
>>>     
>>
>> If TDM to TDM is ok, then it would strongly point towards a problem 
>> with perhaps the VoIP provider.  This is just shooting off of my hip, 
>> but maybe a jitterbuffer issue, like with the phones?  I think when 
>> Asterisk bridges SIP->SIP calls, it doesn't do any jitter buffering.
>>   
> If it is a jitterbuffer, then why the recordings (of the same calls I 
> hear the clicks, not other calls) do not have them?

Well, I could be wrong since I haven't checked the code, but I believe 
that asterisk only enables jitterbuffering on a call if it terminates 
either at a non-rtp endpoint, such as a zaptel TDM interface or perhaps 
a recording to a file.

-- 
Matthew Fredrickson
Software/Firmware Engineer
Digium, Inc.