Lots of crosstalk

[jr6674]

Hello,
I recently upgraded my phone system from XC 5.0 to XC 6.1 to take advantage of the offcore 3rd T1/PRI but ever since we upgraded we have experienced alot of crosstalk . People are calling our 1-800- number (which are 24 analog lines) and they are listening to other people talk at the same time. When we upgraded to xc 6.1 we also upgraded our NAM from 4.0 to 4.1, and our CINPHONY I TO CINPHONY II, has anybody had crosstalk problems before. Your

 

[jr6674]

Also i Wanted to point out that i have another site with xc 5.0 and i had experienced some one complaining about crosstalk, but its rare. Could this crosstalk be because of the analog lines?? its weird bc we never had this problem before until we upgraded to xc 6.1. Thanks.

 

[senk1s]

has it ever happened between intercom calls?
or is it always when a CO is involved?

in a digital tdm switch (like the norstar or your CO maybe 5ESS or dms100) hte possibility of cross talk is very very low ...
unless the software is so corrupt, there is a physical itnerlinkng of lines ...

 

[aragon]

Normally if there is crosstalk on a TDM circuit or switch it is caused because more than one terminal is using the same time slot.
Senk1s' question is valid; are you hearing crosstalk on your intercom calls as well as your outside trunks.
Crosstalk is common on analog lines, especially if there is a ground fault.

If you confirm crosstalk on the intercom paths for internal calls then one would actually hope for something as simple as software corruption and not a software defect in ICS 6.1 software. Nortel is not quick to solve these kinds of problems.
If the problem is due to software corruption you will have to do a startup to clear the corruption.

 

[VencomRob]

I would suspect your CO cabling coming into the building.
24 analog line is a lot of copper. Why not on a T1?

Check the termination block in your space and trace back or have your dialtone people do it.

 

[jr6674]

Thank you all for your response , as far as I am aware all the cross talk is happenning when people are calling from outside on the analog lines, I am not aware of any cross talk between intercom calls. Aragon, When you say that more than one terminal is using the same time slot, do you mean thats happening at the CO or on the ICS, And how would I know if I have a ground fault on my analog line, where do I check. Vencomrob, thanks thats a good point, about checking the cabling, as far as why they chose the 24 analog lines is because they were thinking that if a T1 circuit fail it would stop all calls while the circuit is down, but having 24 analog lines then if 1 fail the others would be available.?

 

[polarbear85]

This really, really sounds like a copper problem...

I've seen crosstalk between two lines because of a short, such as a stray wire trimming on a 66 block, between one wire of each pair.

And I've seen some really weird crosstalk between several lines because we had several bad entrance protectors (typically telco provided) and (perhaps) a not-so-good ground to them. The protectors "blew" and caused a short to ground (which they're supposed to) because of a lightning sort of problem.

So I would ask:
1) did you reconfigure any of your wiring for those lines when you upgraded?
2) does the trouble occur always, or frequently, or just occasionally, e.g. at busy times only?
3) thinking of 2), how do your lines fill up, i.e. on a rotating basis, or is line 1 always first with line 24 used only when all others are busy? The idea is to figure out if just a couple of lines are involved, or if there are several.
4) any chance of rebooting the Norstar during off hours (assuming there are any) to rule out software corruption?

good luck!

 

[senk1s]

first try to identify the lines hwere this happens ...

it is possible that the tip/ring wires are mixed up

 

[aragon]

To answer your question regarding shared time slots:
In your case on analog lines if there was crosstalk on the intercom paths this would point to a TDM problem on the Norstar.
This does not appear to be the case since you claim there is no crosstalk on the intercom paths.

Identify the lines with the crosstalk problem and report the issue to your carrier for repair.