Yealink CP860 SERIES, Administrator'S Manual

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Administrator’s Guide for SIP-T2 Series/T19(P) E2/T4 Series/T5 Series/CP860/CP920 IP Phones
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ensure another line may provide better connection.
Why is there no sound when the other party picks up the call?
If the caller and receiver cannot hear anything - there is no sound at all when the other party
picks up the call, the possible reason could be: the phone cannot send the real-time transport
protocol (RTP) streams, in which audio data is transmitted, to the connected call.
Try to disable the 180 ring workaround feature. For more information, refer to 180 Ring
Workaround on page 430 .
Why does the IP phone play the local ringback tone instead of media
when placing a long distance number without plus 0?
Ensure that the 180 ring workaround feature is disabled. For more information, refer to 180
Ring Workaround on page 430 .
Wi-Fi and Bluetooth Issues
Why is the wireless signal strength low?
Ensure the IP phone and your gateway/ router are within the working range and there is no
obvious interference (walls, doors, etc.) between them.
Why can ’ t I connect the Bluetooth device with the IP phone all the
time?
Try to delete the registration information of the Bluetooth device on both IP phone and
Bluetooth device, and then pair and connect it again. Contact Yealink field application engineer
and your Bluetooth device manufacturer for more information.
Why the Bluetooth headset affects IP phone’s voice quality
？
You may not experience the best voice quality if you use a Bluetooth headset while the 2.4 GHz
band is enabled or while you are in an environment with many other Bluetooth devices. This
possible loss in voice quality is due to inherent limitations with Bluetooth technology.
Firmware and Upgrading Issues
Why doesn ’ t the IP phone upgrade firmware successfully?
Do one of the following:

Ensure that the target firmware is not the same as the current firmware.

Ensure that the target firmware is applicable to the IP phone model.

Ensure that the current or the target firmware is not protected.