IP Office 406v2 ISDN BRI outbound line crackle and popping

[stap78]

Hi

I have an IP Office 406v2 with a 4 port BRI card connected to a BT ISDN2e, we are running digital extensions, and I'm experiencing crackling and popping on outbound calls. Can anyone suggest things to check as I've swapped the cabling, earthed the PBX chassis, checked the UPS, and re punched the krones.

The crackling occurs on outbound and inbound calls across the BRI lines but isn't heard by the called/calling party on the PSTN. Calls internally are crystal clear.

Any thoughts or ideas welcomed.

Could this be to do with ISDN clocking? Or would both parties of the call hear the crackling?

 

[montyzummer]

Get a trend tester on the lines and hammer them with calls to see if you can hear the popping...if not below

Busy out channels one & two make calls with monitor running see if the fault happens .... if it does busy out one and two and recreate with monitor running , log to file and see if the fault follows a port or not.(post your monitor results here whilst running a test with your service provider...yeah right!!....if they will) If it does swap the slot the card is in.

If it still happens two options try a different card.... but first research for similar issues with you Revision of HW/FW and upgrade the kit and card...... trend tester is first stop shop though



APSS (SME)
ACSS (SME)
ACIS (UC)

 

[amriddle01]

Crackling on ISDN is very rare, crackling is by nature an analogue noise. I would put a demo kit or ISDN tester on the line and listen for the crackle on that, I imagine it's actually an issue in the exchange or something

 

[snowman50]

Get BT to test the line..
They can see if there are any errors.

It's probably a noisy pair of wires.
It will need and line engineer out to test and change the pair.

It's still a pair of copper wires and prone to the usuall issues an analogue line has.

 

[intrigrant]

If you have multiple BRI connections the set one as the clock source and the others either as fallback or not suitable.
Take a monitor trace and enable all on ISDN, if it is a sync problem you can see that in monitor, any status message with a "F" code is a problem, these should not been seen on a normal synced ISDN connection.

 

[snowman50]

Try this first.

Make the ISDN lines as line appearances, 701-704 on a phone

Then press the line button to see which channels have the noise

At least this way you can narrow it down to the actual lines if they are faulty.