Troubleshooting – Aastra Telecom MBU 400 41-001286-00 User Manual
Page 63
Aastra MBU 400 User Guide
63
Troubleshooting
There is no audio when I make
Internet calls.
The router blocks audio.
Use port forwarding. Check your router’s
user manual to see how to configure port
forwarding.
I cannot make landline calls.
The landline cable is not connected. Check that the landline cable between
the Line port on the MBU and the
telephone wall outlet is connected
properly.
The landline is out of order.
Contact your landline provider.
I cannot receive landline calls.
The country setting is wrong.
Check that you have chosen the country
that you are in. Open the System
settings menu, choose Country
selection, and then choose the country
that you are in.
I cannot make Internet calls, the
VoIP indicator on the MBU is not
lit, and the right status indicator
in the upper left corner of the
display is black.
The configuration of the phone is
not complete.
Check that you have configured your
phone properly. See
For more information, contact your
Internet Telephony Service Provider or
your System Administrator.
The MBU has not been reset after
you saved the configuration.
Reset the MBU and allow the MBU 2
minutes to log in at your Internet
Telephony Service Provider.
The router uses port forwarding.
Check that you have configured your
router so that it always assigns the same
IP address to your phone’s MAC address
when using port forwarding. Otherwise
incoming traffic is probably not forwarded
to your phone. For more information,
check your router’s manual.
The router blocks Internet
telephony.
Use port forwarding. The default SIP port
is 5060, and the default RTP port is
5004. Ensure that your router always
assigns the same IP address to your
phone when using port forwarding.
For more information, check your
router’s manual.
The router firmware needs updating. Check your router’s user manual to see
how to update the firmware.
When I make Internet calls, the
sound quality is poor.
There is too much simultaneous
data traffic on your broadband
connection.
a) Reduce the amount of traffic on your
broadband connection.
b) Sign up for a Quality of Service
agreement with your broadband
provider.
c) Order a connection with higher speed
from your broadband provider.
Your Internet Telephony Service
Provider’s Quality of Service is
based on a “best efforts” rather than
a guaranteed voice priority method.
Contact your Internet Telephony Service
Provider regarding ensured voice
prioritization across the network.
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