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Crackling only when Recording

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Bucky101

IS-IT--Management
Feb 9, 2006
419
AU
I have a hunt group that when set to mandatory call record the users hear crackling/bad quality voice. When I disable call recording everything works fine.
Any ideas??
 
got to system
telephony
tones and music

and click gsm silence supression

should make it better


ACA - IP Office
ACS - IP Office
ACSS-SME

 
Change these settings

1 For the VCM settings:
  -Set Nonlinear Processor Mode to Disabled.
  -Set NLP Comfort Noise Ceiling to -55

2 In NO User ---> source number put the below string
  CONFERENCE_DSP_TX_GAIN=-3



Homo sapiens non urinat in ventum

honey, i fried the IP Office !!!

Sarcasm, it's only one of the services I offer.
 
Brilliant! Thanks Pete,
For the VCM settings:
-Set Nonlinear Processor Mode to Disabled.
-Set NLP Comfort Noise Ceiling to -55

In NO User ---> source number put the below string
CONFERENCE_DSP_TX_GAIN=-4

works perfectly.
Does anyone know what the CONFERENCE_DSP_TX_GAIN setting actually does to the phones?
 
I've just tried these settings and it fixed the noise but i'm getting an echo now do i need to change the CONFERENCE_DSP_TX_GAIN=-4 to fix this or is there another step ???

BCM/CS1K/IPOffice/Cisco CUCM & CUCME Engineer
 
i have changed it to CONFERENCE_DSP_TX_GAIN=-2, and i did a couple of test calls and the echo has gone away, is this CONFERENCE_DSP_TX_GAIN=-2 supposed to do that ???? or do i need to increase the call sample size and make more test calls.

BCM/CS1K/IPOffice/Cisco CUCM & CUCME Engineer
 
Set it to -3

You can set it between -2 and -5
This has been a long ongoing issue and -3 seems to be the best setting.


Homo sapiens non urinat in ventum

honey, i fried the IP Office !!!

Sarcasm, it's only one of the services I offer.
 
i will need to reboot the system for this to take effect won't i ??

BCM/CS1K/IPOffice/Cisco CUCM & CUCME Engineer
 
>i will need to reboot the system for this to take effect won't i ??

Correct - most (if not all) NO_USER strings require a reboot to activate.



Take Care

Matt
I have always wished that my computer would be as easy to use as my telephone.
My wish has come true. I no longer know how to use my telephone.
 
thanks guys !!!! i'll reboot tonight

BCM/CS1K/IPOffice/Cisco CUCM & CUCME Engineer
 
Did this ever REALLY help?

When there is a VCM channel *and* the conference chip involved in the call, then the sound is bad. Depending on the settings from above it may be not so obvious. But there is a crackling and or noise. Usually only for the internal party and only if he speaks.

We have this on many sites. Solution is welcome.

Regards
Albus
 
>Did this ever REALLY help?

yes

Take Care

Matt
I have always wished that my computer would be as easy to use as my telephone.
My wish has come true. I no longer know how to use my telephone.
 
If you want to say that there is no difference between a normal call (IP-Phone to BRI, G.711) and the same with recording, then I like to see your config.
Even Avaya was not able to fix it. We lost a customer because of this. It has nothing to do with hardware. All parts have been changed several times. It's not related to the release, we started this with 4.2 upgraded to 5.0 and ended with 6.0. No difference.

But some people are more sensitive then others. Some think G.729 sounds good enough. Others complain about every detail...
 
The issue is caused because Avaya re-architectured the call record within the IPO at somepoint in version 4.

We worked on the original issue with our distributor, having identified that the issue was related to call recording. After many iterations and private builds and NO USER codes we achieved a resolution.

This issue is not caused by faulty hardware, but by the process of conferencing. You need to tune the confernce gain to get the best results

Take Care

Matt
I have always wished that my computer would be as easy to use as my telephone.
My wish has come true. I no longer know how to use my telephone.
 
I suppose you have more then one site with recording. Do they all work well with the same parameters or did you need to tweak around to find a special setting that is good for a single site?
Probing all possible combinations is a time consuming process when everything needs a restart...
Did you get a better description of the options then the small description in the help?

I was told to try different values regarding the tab System|VCM and the CONFERENCE_DSP_TX_GAIN=-2 (and other values) as well as GSM silence suppression.
Maybe I was just not lucky enough to find the good combination.


 
You need to use -3
-2 is not good enough and still causes problems.


Homo sapiens non urinat in ventum

honey, i fried the IP Office !!!

Sarcasm, it's only one of the services I offer.
 
Below is the info I got. Which of this is really related to this problem and what will help?

- Enable GSM Silence Suppression – System>Telephony>Tones & Music>GSM Silence Suppression.
- NoUser Source number CONFERENCE_DSP_TX_GAIN=-2
- Adjust the NLP comfort noise ceiling to be -55dB on the system VCM tab.
- And set VCM > Nonlinear Processor Mode to Silence.
- Reboot after saving these changes

This did help, but the customer is still not happy with it.


Now, you recommend to use -3 instead of -2. Ok, will try it.
What about GSM Silence Suppression. Did you need this too?


Am I completely wrong when I suppose that there must be *one* set of parameters, that will do for all systems, when recording is used? Or is it really different for every system?

We have a IP500, ISDN lines, IP-Phones (56xx,16xx, soon 96xx) and good server for VM Pro with CS.


 
This is a hardware and software issue. The comfort noise levels on recorded calls are most definitely different to the levels on a non-recorded call. This is most apparent on IP phones but the issue can be heard on digital phones too. On our test kit (multiple IP500v1s) the noise is not too distracting, but I've heard customer sites where it is very bad (loud white noise, clipping and echo). Some customers are happy after applying the above settings, some say they make no difference. In one instance the problem was fixed by replacing a new IP500v1 and VCM (2009/2010) with an old one (circa 2007), so the hardware is a factor.

All the instances I've dealt with were on IP500s, I don't know if it happens on IP400s. Avaya don't have a definitive fix.
 
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