Mitel 3300 T1 issue

[ralph]

Version 6.0SP1 12.0.1.24
T1 (Not PRI)

All channels are programmed with identical CDN.  Only difference between them is the trunk number and Trunk Service Number.
Channels 1-5 & 24 are working correctly.

Issue is this:  Carrier monitors DS0.  Channels 1-5 and 24 all show all Ones when idle(good).  We attempted to add a new ARD (PLAR) to channel (DS0) 6 but when idle it shows all Zeros (bad).  Channels 6-23 all show Zeros when idle.

We had to move the ARD to channel 24.   All programming matched what was on channel 6.   When on channel 24 it works correctly.
I issued a load command against the T1 card "Load 6 1 3".  No change.

Why would a DS0 that is programmed idential to other DS0s not work the same?
Has anyone seen this before?

Ralph

[lundah]

The only thing on the 3300 that could be different for each channel on the T1 that I can think of is the circuit descriptor on the trunk. Is there a CSU/DSU somewhere in the path that needs channels 6-23 enabled or configured differently? That's the only other thing I can think of.

[LoopyLou]

Have never seen that. As lundah says wonder if its the carriers equipment in that maybe you have to get them to turn something up to get the additional channels.

[acejavelin]

Same... that's a new one. If the CDN is the same there isn't really anything you can change to make them different. Sounds like an issue on the carrier end/CSU/channel bank or whatever is feeding the T-1.

[ralph]

You're all coming to the same conclusion I am.
There isn't any reason for the issue on the Mitel end.
I can't think of what the carrier would be doing to cause it either.
Possible bad hardware on Mitel end?

I'm thinking next step is to be on site with a T1 tester and test local to the PBX.

Ralph

[lundah]

I've never seen a hardware failure on the Mitel that would only impact specific channels on a circuit. I'm assuming the system has enough DSP and E2T resources as well. The only thing I can think of that would effect individual channels like that would be a CSU/DSU.

[ralph]

The only thing I can think of that would effect individual channels like that would be a CSU/DSU.

Or lack of one?

Ralph

[lundah]

The only thing I can think of that would effect individual channels like that would be a CSU/DSU.

Or lack of one?

Ralph

Well on the Mitel end you don't need one because the T1 card handles the functionality. But what's on the other end?

[ralph]

The T1 routes to the carrier.  From there the carrier breaks out the DS0s and sends the calls to other T1s/customers.   So from most of the channels it simply ends at the carrier.   They've been able to check DS0s and see what bit's we're sending.

Ralph

[lundah]

Well in that case the obvious first place to look would be whatever device on the carrier end the T1 terminates to (I'm assuming a digital cross-connect system of some sort), since channels 6-23 are obviously optioned differently than the rest somewhere along the path.