There is also a software bug that I have ran into between a 5000 and an Axxess. It may or may not relate to this situation but I posted the notes I have:
The Axxess IPRC has an unsupported fax pass-through mode for IP private networking. In this mode, the IPRC detects a fax tone and switches the encoding to G.711. The IT-5000 uses T.38 for fax-transmission for IP private networking. These methods are not compatible. Attempting to use them together will result in Insufficient Bandwidth Alarms and one-way or no audio.
There is also a bug in some Axxess versions that sets the Fax Detection Sensitivity to 1 when it is programmed to 0 (off, the default) in the database. This causes frequent erroneous Insufficient Bandwidth alarms to occur.
In Axxess, the settings are in OLM mode under Node IP Connection Groups-P8xxx-IP Call Configuration.
There is a chance of false fax detection when the Fax Detection Sensitivity level is set to a low value. It seems common for the sensitivity level to be set to 1 (10 ms) which will result in frequent false detections.
When networking Axxess and IT-5000 nodes, both sides should have fax detection maximized - As a precaution to avoid the known Axxess bug, set the Fax Detection Sensitivity to a value of 100 (100 is maximum) on all Node IP Connection Groups (P8xxx) on both the Axxess and IT-5000 nodes.
NOTE - IT5000 to IT-5000 or Axxess to Axxess, this does not need to be set.
Examine the Network Diagnostics Log (.ndl) on both systems for a good indication that this is happening. This log shows Insufficient Bandwidth Alarms. If one system has the majority of the alarms, there is a good chance that the opposite node has incorrect fax settings.
This only applies to IP private networking calls with a combination of IPRCs and IT-5000s. Insufficient Bandwidth Alarms on IP endpoint, Axxess-only, or IT-5000-only calls probably have another cause.
