Digium Phones D50 and D70 in Feedback Loop

Hello All - Question for you. Has anyone ever had an issue with a call ending up stuck in a feedback loop? I’m having this issue between certain phones on our network.

Phone A - Digium D70
Phone B - Digium D70
Phone C - Digium D50

Any calls between Phone A and Phone B, or between Phone A and Phone C almost instantly degrade to just pure audio feedback in the handsets. Nothing can be understood because both phones start squealing. Hitting the mute button on either phone breaks the loop and stops the feedback, but as soon as you unmute it and say anything into it, the problem returns.

The thing is, phones A, B, and C all work fine for calls to other internal and external phones, it’s only certain combinations.

Anyone ever run into this before? Any suggestions on what to try next? Is it likely a hardware issue?


Please contact Digium’s Support department directly - www.digium.com/support


I have only ever experienced this if I am testing two phones in conversation on speaker that are right next to each other. I’ve never had a real world situation where this happened.