ISDN PRI T2 Incoming Calls with Echo

[enrique.man]

Hello Guys,

Hope you guys are doing well and wishing you a Happy New Year 2021 !! with a lot of health and hoping this one is better than the last one.

I am having a issue at a customer site where random incoming calls cannot been heard. When receiving an incoming call, we can see that the call is established and connected , but cannot hear each other, it is some kind of echo where i can just hear myself speaking. From 10 calls , 2 calls are presenting this issue approximately.

The customer has an OXE R12 with a T2 Trunk Group.

I took some t3 traces and I´ve been analyzing them but with no success. The only difference seen is in the normal call clearing step where one has a Progress ID and the other one not.

|______________________________________________________________________________
|
| IE:[08] CAUSE (l=2) 8a 90 -> [90] NORMAL CALL CLEARING
| IE:[1e] PROGRESS_ID (l=2) 82 88
|______________________________________________________________________________

and

|______________________________________________________________________________
|
| IE:[08] CAUSE (l=2) 81 90 -> [90] NORMAL CALL CLEARING
|______________________________________________________________________________

Attached the traces, hoping someone can help.

Regards,
Enrique

[haroun]

Is synchro well ?!it seems the lost of packets!
public isdn or private? try another board

[enrique.man]

Hi Haroun,

It is a Public ISDN. Thanks for the recommendation, i´ll try another board and let you know the results.
If same issue, any other suggestion?

Regards
Enrique

[haroun]

Hi Enrique
can you post trkstat Cristal N° coupler position n°
and infocs commands
exemple trkstat 0 8
Trunk Grp 2003 2003 2003 2003 2003 2003 |
| Channel 26 27 28 29 30 31 |
| State F F F F F F |
+------------------------------------------------------------------------------+
| F: Free | B: Busy | Ct: busy Comp trunk | Cl: busy Comp link |
| WB: Busy Without B Channel| Cr: busy Comp trunk for RLIO inter-ACT link |
| WBD: Data Transparency without chan.| WBM: Modem transparency without chan. |
| D: Data Transparency | M: Modem transparency |
+------------------------------------------------------------------------------+
| ALARM COUNTERS |
+------------------------------------------------------------------------------+
| NOS | AIS | LOS | FEC/CEC | RAI |
| 13 | 3 | 0 | 0 | 0 |
|------------------------------------------------------------------------------|
| NOS : no signal | LOS : loss of synchronization |
| AIS : alarm indication signal | FEC/CEC : Frame/Checksum error counter |
| RAI : remote alarm indication | |
+------------------------------------------------------------------------------+


(1)pst_cpu20> infocs

Tue Jan 5 15:10:54 CET 2021


+----------------------------------------------------------------------+
| N_CR | N_CPL | TYPE | N_ACCES | PRIO | SYNC_CLOCK | TG/LK |
+----------------------------------------------------------------------+
| 0 | 18 | PCM2 | 0 | 9 | SYNCHRO | TG:1800 |
+----------------------------------------------------------------------+

+---------------------------------------------------------------------+
| Synchronization on global domain |
+---------------------------------------------------------------------+


+========================== Synchro DECT ==================================+

+--------------------------------------------------------------------------+
| N_CR | N_CPL | TYPE | DECT_CLOCK | Depending Crystals |
+--------------------------------------------------------------------------+
| 0 | 6 | CPU7_STEP2 | DTM PRESENT | |
| 0 | 20 | CPU7_STEP2 | DTM SYNCHRO | 1 2 3 4 |
+--------------------------------------------------------------------------+