* Please use 5V power adapter comes with your cell phone. 
​Most of the aftermarket(cheap) 5V power adapter will introduce noise in audio.

* Lower your cell phone Bluetooth audio volume to 25%after the call connected to avoid echo.
You only require to setup once. Also, Bluetooth audio volume setting won't affect your cellphone normal audio volume.

​​* ​If ringing and dialing OK but NO AUDIO,
​please make sure your cell phone audio's option is in "auto" or "Bluetooth"

* Enable "media audio" by pressing 61# from your home phone keypad.
The default audio stream is using mono. The audio quality may be improved if select "media audio".  However, all media sound such as music will route to you home phone.

* If your home phone comes with an external power supplier, please use external power.

Please check the version number printed on the back of your device.
If you have Version 4.0 or higher, click here to update the firmware
which allow you enable many new features such as "DTMF command enable", "Robot call block", "Speaker and Mic" volume adjustment, "ring power" increase, "off hook power" increase....

If still have problem, feel free contact us at support@cell2jack.com