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Echo on external calls only

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Ekudeht

Programmer
Jul 22, 2011
5
US
Members,

I have a user who is only experiencing echo on external calls, internal calls are clean. Any suggestions on where to begin troubleshooting such a request?
 
are you compressing the external calls? Is this just on IP devices or TDM devices also?
 
Bobcheese

Thanks for your reply

1: Very new to telephony, where would I find that info in OPSMAN 3300ICP?

2: All phones are IP (5330 or 5212)
 
Compression won't affect the echo.

The type of trunk will however. Are they LS trunks or digital? If they are LS trunks, have you run the Line Measurement Tool? If so, what did it report? If they are digital trunks, it's a trickier proposition. Normally in that case it's a lack of echo that causes the echo (if that makes sense to some). To narrow it down, what type of trunks do you have?
 
I believe after searching I have discovered they are digital as LS settings configured and all of our sites are connected by T1 or fibre
 
My appologies... I think they are digital because the LS settings are empty
 
If they are digital trunks then you may want to get your SP involved to verify the trunks. The 3300 also has the capability of hardware or software-based echo cancellers, each with their own merit. That however is something best left to their support to figure out.

If it's a digital trunk, one of two things are happening. Either there is too much echo for the system to suppress, or there is a small amount of echo, so small that the echo cancellers don't detect it but when you add the IP delay, it's noticeable to the user.

There is a third reason, and that is that the far end is on a cell phone or hands-free device. Make sure you do a test call to a well known POTS device to make sure it's not user error on the far end...
 
Did it happen once or does it happen consistently? I had a situation where a call came in to our 6160, was disconnected, and then immediately reconnected as another call. The port being used by the disconnected call was never released by the 6160 and it combined both calls together, causing the echo. It's a pretty rare occurance but I've seen it happen more than once.

Does the site have call recording that would enable you to verify the frequency of this echo problem for this particular user? Certainly wouldn't be the first time a user reported something "always" happens after the first occurance ;)
 
How are your digital links presented?

This could be an NTE issue, Ive experienced this depending on the kit that the network provider has terminated the lines on.

Trunk side recording would be the best piece of kit to prove either way, or even an ISD30 tester where you tap into the NTE.
 
Interesting its only one user. Is it really only one user or is it just no one else has complained? If its one user do they get it on all external calls? If not is it only a couple of numbers? Spent time chasing one issue like this only to find when talking to the user its only a couple of numbers and both are cells.

Handset or headset? Remove headset and test if present.

Does the user have a hearing aid by any chance?



The single biggest problem with communications is the illusion that it has taken place.
 
Many thanks to Irwin and LoupyLou (and all others who read and responded) for illuminating step one of any telecommunications troubleshooting venture...

Test first against a known good PSTN.

The user in question primarily contacts cellular clients and on the day in question it appears that the "multiple calls" that received the echo were to cellular clients... who just so happen to use the same provider... and were in the same building as the caller at the time in question.

Thanks again
 
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