One way Audio Panasonic KX-NCP500 Linear AE-100 call box.

[Dave Parrish]

I have a strange issue with one way audio the setup is a Panasonic KX-NCP500 with 4 antilog trunk lines that work fine with all calls coming in except when the system is called form a Linear AE-100 call box that dials into the system from a trunk line from another business that the building is leased from. The call box dials the system fine when the KX-NCP500 picks up the call they cannot here the caller but the caller can hear them.
This only happens with the call box the company claims that they tested the call box and it works with other tenants in the building.
I tried a butt set on the trunk line coming into the KX-NCP500 and it works fine but when it goes though the KX-NCP500 I get the one way audio issue.
Any thoughts

 

[obtsystems]

It sounds like the ring burst is short and when you answer the system thinks Its an out going call and will mute the mic

To test this dial 123456 on the key pad when you answer.

If this works change the ring timer in card properties