Nortel, Speakerphone automatically going off hook

[Jay102]

We have a CS1000 that has an odd problem in that for no apparent reason various phones throughout the campus will go off hook on speakerphone. They have been known to dial various numbers but most times will just give ringtone. This will occur numerous times and we end up redoing the cable path and TN but the problem is becoming increasingly widespread. All we are really doing is addressing the symptoms and not correcting the problem. The worry was water intrusion in the 600 pair that was causing a short and this issue but we have transitioned from that cabling and issues continue. This occurs with numerous and buildings so it is not likely that all cabling has been flooded. Admittedly we are close to sea level but none of the cabling is in flooded vaults so there is no definitive smoking gun. All lines from the PBX have lightning protection as grounding was a concern as well. All phones that are affected are 3904s and the sound quality is not diminished in any way.

Does anyone have any wild ideas what may be occurring or causing this?

Thank you for any help,
Jeff

 

[LDantalion]

We have a SL-100 with about 2500 phone drops. It is happening exactly the same way you explain it, but no specific pattern. From my limited experience, I can tell you however that all of the faults we have found so far are due to connectivity issues either on the ICP or OCP. If you are trying a different cable and it still persists, I would recommend testing the ICP blocks or even repunching the copper pairs in the primary or secondary OCP boxes and customer premises to avoid any short circuits. We are also running on old copper cables to some areas and sometimes the technicians do bad punching, which causes this type of problem.

 

[trvlr1]

You might want to check out your grounding, make sure it is solid and reliable and not tied to something that does not have a reliable ground.

 

[RickyPone]

I'm assuming this is happening across different superloops and even diferent network groups? If so what happens if you wire a few phones directly off of the tn frame in the equipment room? If the problem persists then you know it is not a cabling issue. If no troubles then there you go. What about switching the cores? Does it happen on core 0 and 1? If the trouble is isolated to one superloop then just change the controller or the network card.