sundance-communications.com/forum Forums TDM Business Telephone Systems Mitel Telephones & Systems Feedback on Call with Music on Hold

To start off, I am not completely fluent in Hardware PBX, the programming end of the Mitel or the intracacies of the hardware types.

We are using an SX 200 with two T1 cards. The first T1 card is in the top cabinet connected to a voice T1.

The second T1 card is in the bottom cabinet (lightwave?) and is connected to an IP PBX (asterisk).

There is a Music on Hold device in the bottom cabinet. When you make a call into the Mitel using the voice T1 and are placed into hold, you can hear the Music. When you place a call into the Mitel through the Asterisk server and are placed on hold you hear awful feedback.

We switched the T1 cards and circuits and the problem stayed with the cabinet, that is to say when we switched them, the calls over the voice T1 came into the bottom cabinet and heard feedback while the music was supposed to be heard. And the calls coming into the top cabinet over the Asterisk facing T1 card could hear the music fine.

Our hardware vendor is going to bring in a new cabinet to test but I wanted to check with this forum to see if anyone has had this type of problem before.

Are there any settings to offset this feedback?

Thanks!

What model sx200 do you have? May be related to dual/triple fim setting in form 4

Hi John,

Here is the response I received on your question from the location with the Mitel:


UPDATE: We have an SX200-D EL with SW version 19.2 and the cabinet is a lightware peripheral node.

[This message has been edited by geoffm33 (edited June 16, 2005).]

The next thing to verify is whether the card that connects the cabinet is a dual or triple fim. Also check the tenating of the trunks and make sure they all use the same music source. If one is using an unplugged dmp as its' source a terrible noise will be heard.

I think that may be it. We have a HW support guy that has been trying to solve this with us and when we mentioned this to him over the phone a light went off in his head that it could be the cause. He will come in to morrow to check. Unless this is something easy to do in which we can have the company tech try it.

Thanks for all your help!

That was exactly it, it is up and running with no static now. Thanks a lot for your help!