sundance-communications.com/forum Forums TDM Business Telephone Systems Mitel Telephones & Systems Mitel 5000, popping, hissing on digital lines

Sometime during the night, the T1 card in my companies Mitel 5000 died. We fixed it by swapping the card with a working one from our local vendor who had one in stock because that is how they troubleshoot, buy parts and throw them at the problem until the unit works.

So,our system is working again, but we are getting bizarre interference on all of our digital handsets (our IP phones are working perfectly). It sounds like popping, hissing, etc.

We have changed no programming, just shutdown and swapped a card. Everything at the physical layer is fine, as it has not been changed, and I have verified the integrity of all the connections from the demarc all the way to the DEM-16 on the back of the box.

None of the local guys do Mitel, and the initial installers had been practicing (never done it before) when they got us running. C'est la vie.

Any ideas?

Does the problem exist between two phones ( not useing an outside line x101 to x102) or just when calls are connected to the outside world?

All calls; if a digital handset is anywhere in the equation, the problem persists. Calls to the outside, calls between two digital, calls between one digital and one IP, etc.

If the calls from phones to trunks were your only problem then the t-1 or t-1 card would be suspect. If you are having the same problems between digital sets and digital to IP then you may have a bad digital card, peripheral control card. if IP to IP works then that would eliminate the controller in my book. I would suggest contacting a qualified Mitel dealer to assist in the trouble shooting

We only have one Mitel dealer in the area, and they are not... going to help. I have been working with Mitel direct through their Reno office and they are sending us out a new DEM-16, we had arrived at your same conclusion after much troubleshooting.

If the new part doesn't fix it, and nobody on here has any ideas, we will be bringing in out of state help from California.

Please keep us informed, we do like to hear if the problems get resolved

Potentially you may have had a power surge or some sort of strike that not only took out your T1 module, but damaged the digital module in your controller. Since all audio between IP terminals are handled by the IP terminals themselves, and the calls between IP terminals and the outside world bypasses the DEM but flows throw the T1, via the controller DSP,...it seems you are on the right track by replacing the DEM...unless you have more than 16 digital phones...

Have you tried moving your DEM to one of the other slots on the controller, eliminating a connection problem where it plugs in?

Jim

Jim

@AKroger: Sorry, I was in Seattle for a few days and couldn't get back at this thread for a bit. We replaced the DEM-16 and now everything works perfect. Thank you for all the help.

@Crowtalks: Yes, we tried swapping bays, no luck. It works after replacing the unit.