I have a NEAX 2400 MMG which has clocking errors daily which show on the alarms on the system. These errors have been showing ever since the system was installed over 10 years ago.
This is now having an adverse effect on an additional switch that we now have on campus which is linked to this MMG over CCIS. As a result the 2400 IPX which is connected to it via CCIS has digital line failures and CCIS link failures due to the system messages and failures that come from the MMG (specifically on the clocking). The messages show that it has frame slips which are caused from the clocking errors and they come from the MMG.
These frame slips result in voice loss when making calls over the CCIS on station to station calls. The call goes through to the other switch, but when the party at the other end answers - neither can hear each others voices. Then both parties hang up and call again and it's fine again. This happens too many times a day though and it's pretty aggrivating to the users!
IN looking into this further, I found that the MMG has the PA-CKOO (clocking card) has setting on the dip switches which mean, "WHEN RECEIVING SYNCHRONOUS CLOCK SIGNALS FROM OTHER OFFICES VIA THE 24-CH DTI CARD:
The dip switch settings I have, mean the following in this category:
"When receiving clocks from two offices".
What I don't understand is if this means that the switch is clocking from two sources at the same time? If so - is this correct? I.e., what if the two sources of clocking aren't actually in synch? Would this cause a scenario like we are having now?
I want to be able to correct this clocking erroRs - but all I have found in the manuals is about replacing the card but the card itself, doesn't appear to be the problem - but possibly the settings.
Any ideas? Suggestions on how to go about correcting/troubleshooting this without adversely effecting the rest of the switch - as we don't see these errors particularly causing any other problems - so in the effort to fix this one, we don't want to cause problems on any other outgoing calls, or station to station calls within the MMG - as this hasn't been a problem.
Thanks.
This is now having an adverse effect on an additional switch that we now have on campus which is linked to this MMG over CCIS. As a result the 2400 IPX which is connected to it via CCIS has digital line failures and CCIS link failures due to the system messages and failures that come from the MMG (specifically on the clocking). The messages show that it has frame slips which are caused from the clocking errors and they come from the MMG.
These frame slips result in voice loss when making calls over the CCIS on station to station calls. The call goes through to the other switch, but when the party at the other end answers - neither can hear each others voices. Then both parties hang up and call again and it's fine again. This happens too many times a day though and it's pretty aggrivating to the users!
IN looking into this further, I found that the MMG has the PA-CKOO (clocking card) has setting on the dip switches which mean, "WHEN RECEIVING SYNCHRONOUS CLOCK SIGNALS FROM OTHER OFFICES VIA THE 24-CH DTI CARD:
The dip switch settings I have, mean the following in this category:
"When receiving clocks from two offices".
What I don't understand is if this means that the switch is clocking from two sources at the same time? If so - is this correct? I.e., what if the two sources of clocking aren't actually in synch? Would this cause a scenario like we are having now?
I want to be able to correct this clocking erroRs - but all I have found in the manuals is about replacing the card but the card itself, doesn't appear to be the problem - but possibly the settings.
Any ideas? Suggestions on how to go about correcting/troubleshooting this without adversely effecting the rest of the switch - as we don't see these errors particularly causing any other problems - so in the effort to fix this one, we don't want to cause problems on any other outgoing calls, or station to station calls within the MMG - as this hasn't been a problem.
Thanks.
