Frequently asked questions (FAQs)

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Product Troubleshooting

Problem:

I am using my VoIP box to set up my wireless home phone and other network devices. All devices work normally except my phone, which has no dial tone/ displays Line in Use with busy tone/ poor sound quality. What should I do?

Solution:

Tip 1 of 1

Despite your VoIP box shows full signal strength, there could still be no dial tone/ display Line in Use/ etc. This may due to the abnormality of signal and voltage levels. Follow this short video to reset your VoIP box and its connected devices.

(For non-IS8151 series - all other models) https://www.youtube.com/watch?v=mXbXl4froUc&t=25s

(For IS8151-X series) https://www.youtube.com/watch?v=rJ9PNkwBzfE&t=3s

[Background]
VoIP box connected via SIM/ LAN connection.
Some VoIP boxes have displays and some not. While displays show steady ON and ready, you might still experience with no dial tone sound/ display Line in Use.

[To Reset]
Some Power off button does not fully power off the unit. It only put the VoIP box in standby mode. To truly power off, unplug the power adapter of your VoIP box.
Disconnect all devices from the box. After a moment, reconnect your power adapter, and then press power button to turn ON.
Wait until the VoIP box is steady ON and ready.
Connect your telephone cable from your Telephone base to your VoIP box.

REMINDER!!!
Make sure you didn't connect the telephone cable from the Telephone wall outlet to VoIP box telephone port!!! Doing so will not damage the device, but it will affect the call function and becomes unusable. This is why you experience no dial tone, Line in Use with busy tone, etc.
During power outage, your landline phone will not be available since it requires external electric power despite your VoIP box has a backup battery.

If this situation persists, contact your VoIP / VoIP box service provider for further support.

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Note:


You may want to reference your product manual.