Bad Speech Quality on 3300CX

[enktr]

Hi All,

System 3300CX, version 9.0. i have 1 port ISDN/PRI and 12 Analog External line. this problem for internal calls and external calls.

Problem;

- Ip Phone to Ip Phone --- Good Speech Quality (Same Switch)
- Ip Phone to Analog Phone--- Sometimes parasite
- Ip phone to External ISDN or Analog --- Sometimes parasite...


Note: Ip phones are 5340s and 5212...

Any Idea????


Best Regards...

 

[enktr]

any idea?

 

[Mitelpassion]

try reloading the software. not seen this before but on the Cxi the software does a lot of things that hardware does on Mxe's

it would appear that whenever there's E2T happening, you have issues. in other words when the controller is involved in the call. Could well be a processor fault too.

don't think it's network related however it could be a the port that the controller is connected to...
taking wild guesses here, good luck

 

[enktr]

hi,

i tried reinstall the software, and i changed the controller, but not solved the problem... i'm using the default paramaters on cos and system options...

any idea?

 

[Mitelpassion]

have you tried moving the controller to a different port

 

[enktr]

hi,

yes i tried with different switch, but problem not solved...

Regards..

 

[Mitelpassion]

do you get the same effect when you dial voicemail?

 

[enktr]

hi,

i tried, there is no problem for voicemail calls (from ip and analog phones)

 

[Mitelpassion]

unless the knowledgebase on MOL has something I'd suggest logging this with Mitel support

 

[IrwinMFletcher]

The first thing they will ask you is 'what is a parasite?', you'll need to be more specific as to the effect of the problem.

Is it static? warbly voice? cut-offs? echo?
Is it at the start of the call? throughout? random?
Are the calls compressed?
Are there any software logs?
Who hears the bad effect? IP? Analog? Both?
Handsfree mode?

These should be standard questions that they ask, so be prepared.

 

[tlpeter]

Is the system grounded ?
Analog trunks can give problems with ipphones

ACS - Implement IP Office
ACA - Implement IP Telephony -- ACA - Design IP Telephony
ACA - Voice Services Management
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[enktr]

Hi IrwinMFletcher,


1) it's not static, din with speech.. there is no echo..
2) it's random..
3) Calls not compressed..we haven't ant comppression license
4) No software logs
5) When i call ip extension to analog extension or External line(Analog External or ISDN/PRI), bad effect heared from only analog extension and external line. Good speech quality for IP Extension...

3300cx connected to directly UPS (without additional Ground) is it problem?

Regards...

 

[IrwinMFletcher]

What is 'din with speech'? Hopefully a typo or I'm lost....

Also, to clarify, by random you mean random bursts throughout a call, correct?

If it's only heard on the TDM side, then that's good. That means that it should be an easier thing to solve since it's most likely a hardware/external interference source. Grounding the system is a good place to start.

Most people report bad audio on the IP side as there is the extra delay introduced by the IP transmission that can increase the effects of the problem.

I would try to isolate the source by moving you trunk groups to terminal/circular and monitoring if it follows a particular trunk.

 

[enktr]

Hi Irwin,

Before starting to apply your recommendations, i want to clarify the situation again in more detail in case of i'm failed to explain it clearly.

Test 1- originating an external call from an analog extension through an analog trunk line or ISDN trunk line.

there is no noice heard from both parties..

Test 2- originating an external call from an Ip extension through an analog trunk line or ISDN trunk line.

A random (not continuos) noise is heard by the called (external side) party..

Test 3- Originating a internal call from an ip extension to an analog extension or vice versa.

A random (not continuos) noise is heard by the analog party...

I hope this time i'm succesfull to explain the problem in more detail. Now after providing these test results i'm waiting your suggestions for solving the issue..
Do you still think that, it's a grounding problem and i should connect additional external ground...

i will appreciate for your quick response...

Thank you very much in advance...

Best Regards...

 

[IrwinMFletcher]

In terms of the 3300, there are two things that are involved when you do test 2 and 3 that are not when you do test 1, and they are the E2T and the echo cancellers. As I mentioned however, when these parts are introduced it's usually the IP endpoint that complains about problems since short burst of echo or disturbance are made more audible by the IP delay.

In the CX another difference from the mainstream controllers is that the default echo cancellers are software based, but from a IP to local TDM analog endpoint (off of an AMB I'm guessing?) so there should be no issues with it. And again, that should only affect the IP side.

I'm still not sure what you mean by bad audio, can you be more specific?

One test to try is to do a conference between 3 IP phones. This will use the same components (E2T, echo canceller) but won't use the AMB and ONS endpoint. See if you still have the problems in that case.

Also, I would suggest that you properly ground your system regardless, independent of the audio problem.

 

[enktr]

Lets define it as scratchy. For example the other party says, " it was a beautiful party" but you hear it as " it was a beaticzfulkz party" and this scratchy sound is not heart every time . Maybe 3-4 times in a 2 minute call.

I will try a conf. call with three IP phones and inform you about the results ASAP.

Until now, I only heart this scratchy sound from analogue end points, (either from a trunk or extension).

 

[tlpeter]

Sound like a broadcast true your calls

ACS - Implement IP Office
ACA - Implement IP Telephony -- ACA - Design IP Telephony
ACA - Voice Services Management
______________
Women and cats can do as they please and men and dogs should relax and get used to the idea!