ISDN Link + Adtran ISU 512

[KLCrgb]

I have a C40 with an ISDN_Link connectivity to an ADTRAN ISU 512 (4 BRIs).  The system works well when dialing video calls.  However, when I try dialing an audio call, it will not connect.  Looks like it tries to make the call, but disconnects within 1-2 seconds.  Firmware TC7.3 and L1.1.5. Am dialing using the Cisco remote with on screen pop-ups.

Anyone have any ideas?  Any help would be appreciated.

[Wayne DeNardi]

Check with your service provider that you have Voice Calls enabled on the ISDN Service you have purchased from them.  Some ISDN services are not configured for Voice and/or Data transmission unless specifically requested.

This has been the cause of a number of these issues I've seen before where Voice worked and VIdeo didn't, or the other way round.

If that doesn't help,are you able to connect the BRIs directly to the ISDNLink rather than connecting them through the ADTRAN?

Wayne
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