Specifications

Troubleshooting
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If you have poor sound quality/acoustics like intermittent voice, low volume, echo or
other noise, the possible reasons could be:
 Users are seated too far out of recommended microphone range and sound faint,
or are seated too close to sensitive microphones and cause echo.
 Intermittent voice is mainly caused by packet loss, due to network congestion, and
jitter, due to message recombination of transmission or receiving equipment (e.g.,
timeout handling, retransmission mechanism or buffer under run).
 Noisy equipment, such as a computer or a fan, may cause voice interference. Turn
off any noisy equipment.
A remote phone book is placed on a server, while a local phone book is placed on the
phone flash. A remote phone book can be used by everyone that can access the server,
while a local phone book can only be used by a specific phone. A remote phone book is
always used as a central phone book for a company; each employee can load it to
obtain the real-time data from the same server.
Both user name and register name are defined by the server. User name identifies the
account, while register name matched with a password is for authentication purposes.
Display name is the caller ID that will be displayed on the callee’s phone LCD screen.
Server configurations may override the local ones.
IP phones support remote reboot by a SIP NOTIFY message with “Event: check-sync”
header. When receiving a NOTIFY message with the parameter “reboot=true”, the IP
phone reboots immediately.
The message is formed as below:
NOTIFY sip:<user>@<dsthost> SIP/2.0
To: sip:<user>@<dsthost>