Inter-Tel AXXESS Manual page 1346

Troubleshooting
® ®
INTER-TEL AXXESS
Table 7-21. IP Networking Troubleshooting Chart (Continued)
Symptom
No audio on network calls
Phone display shows
INSUFF BANDWIDTH FOR
VOICE
One-way audio on network
calls
Poor call quality on network
calls
DTMF tones are not detected
The network is experiencing
audio and/or connection
problems
Cannot fax across the net-
work
Page 7-66
MANUAL VERSION 11.0 – May 2008
Possible Cause
Two NATs or firewalls are
present in the path.
The audio stream receive
ports are not programmed
correctly.
The IPRC is faulty.
The Ethernet cable came
unplugged from the IPRC
and/or data network (i.e.,
hub) during a call.
The data network does not
meet the minimum specifica-
tions required for IP network-
ing.
The data network is experi-
encing problems (e.g., exces-
sive packet loss and traffic).
A NAT or firewall is present
in the path.
The audio stream receive
ports are not programmed
correctly.
The data network is experi-
encing problems (e.g., exces-
sive packet loss and traffic).
The data network does not
meet the minimum specifica-
tions required for IP network-
ing.
The G.711 vocoder is using
too much bandwidth.
The G.729 vocoder is com-
pressing audio data, resulting
in poorer quality.
DTMF tone length is too
short.
The wrong DTMF vocoder is
programmed.
There is a port conflict or the
firewall, NAT, or router is
blocking the port.
Currently the IPRC does not support faxing over the IP network.
Corrective Action
Remove the NATs/firewalls. The IPRC cannot work
behind firewalls or use NATs. See
details.
Make sure the audio stream ports fields match for
the affected nodes. See page 6-177
Replace the faulty IPRC.
Make sure the Ethernet cable is plugged into the
IPRC and data network.
Run the Network Qualifier to assess your data net-
work. Then verify that your data network meets the
minimum specifications (see
information).
Contact your network administrator.
Remove the NAT/firewall. The IPRC cannot work
behind firewalls or use NATs. See
details.
Make sure the audio stream ports fields match for
the affected nodes. See page 6-177
Contact your network administrator.
Run the Network Qualifier to assess your data net-
work. Then verify that your data network meets the
minimum specifications (see
information).
Switch to a G.729 vocoder, which uses less band-
width.
Switch to a G.711 vocoder, which does not com-
press audio data, resulting in higher call quality.
Set the DTMF Digit Duration/Pause field to 100ms
or higher (see page 6-331).
Make sure the DTMF Encoding field is set to either
G.711 or RFC2833 (see page
Try changing the ports associated with IP call con-
trol and/or audio. Make sure none of them conflict
with ports that other protocols use (e.g., SIP uses
5060).
page 2-94 for
for details.
page 2-94 for more
page 2-94 for
for details.
page 2-94 for more
6-186).
IP Networking Issues