[asterisk-users] Customer complains of noise on line I cannot reproduce.

[Eric Wieling]

Could this be ECFO?

Echo Canceler Freak Out, this happens when the rxgain is too high and 
the echo canceler freaks out.  Some users describe it as "screeching", 
"feedback", "static", or other useless terms.  If users report "static" 
on a system where there cannot be static (all digital, PRI, SIP, etc), 
you might be experiencing ECFO.

Try lowering your rxgain and txgain.

Fons van der Beek wrote:
> Perhaps irq sharing?
> 
> Royce Souther schreef:
>> I have setup a few Asterisk systems for customers using Digium TDM400 
>> cards and Aastra phones. No problems with sound quality at all except 
>> at this one site.
>>
>> Every time I try their system I don't hear any problems but they tell 
>> me that it is really bad. They describe it a a loud scratching sound.
>>
>> Are there any tests that can be done to pinpoint the problem? Has 
>> anyone seen this before? Are there known causes for this?
>>
>> -- 
>> Open Source: To innovate then create
>> Proprietary: To imitate then litigate
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>>
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