DX3 Pro+

· Check the power connection.

· Try with another DC15V power adapter.

· Try with another power outlet.

‍

· The device did not power on. Check the power supply.

· Check that the proper input source is selected. Press the knob on front panel to switch input channel.

· Check the output setting. Doule-press the knob to switch output channel.

· Check the connections for all devices.

· Insert connection cables all the way in.

· Check the volume of all devices and whether they are muted.

· Bluethooth IN: Too low volume on phone. Please adjust volume.

· USB IN: 1) Too low volume on PC. Please check and adjust the computer system volume, music player volume and driver volume. 2) Select the default output device of your music player or computer as this unit.

‍

· Try with other songs.

· The specifications of songs are not supported by this unit.

· If the noise appears only when playing DSD files, please check and adjust the computer system volume, music player volume and driver volume to the maximum.

· Check to see if the problem is with the source, downstream equipment and cables.

· If the noise disappears after unplugging the USB cable, it may be interference from the source. You could try to add a USB isolation between this unit and the source.

‍

· Check to see if the problem is with the source, downstream equipment and cables. You can try swapping the left and right channel connections and try with another source.

‍

· Check to see if the problem is with the source, downstream equipment and cables. You can try swapping the left and right channel connections and try with another source.

‍

· Enable Bluetooth function in the setup menu first.

· May be already connected to another Bluetooth device. Press and hold brightness button in the lower right corner on the remote to let this unit enter pairing mode.

· Bring the Bluetooth device near to this unit.

· Turn the power of the unit off and on again, and then try again.

‍

· Bring the Bluetooth device near to this unit.

· Remove obstructions between the Bluetooth device and this unit.

· To prevent electromagnetic interference, locate this unit away from microwave ovens, wireless LAN devices and other Bluetooth devices.

· Reconnect the Bluetooth device.

‍

· USB cable did not connected properly. Please check or change the cable.

· Try with another USB port.

· Driver problem. Try to reinstall the driver.

· May be caused by the PC. Check or try with another PC.

· Some phones require OTG function to be enabled first.

‍

· Try to insert two fresh AAA batteries.

· Please aim at the remote control receiver.

· Bring the remote control close to the device.

· Use your Android phone's camera to look at the transmitter at the top of the remote, if it doesn't blink when you press the remote button, the remote is defective.

· If you have more than one Topping device, check that you are using the correct remote control.

‍

· The choice of music player app, the setting of music player and the setting of computer/phone will all have an impact on the sampling rate.

· The sampling rate displayed by this unit is the sampling rate of the input signal, and it will not change the sampling rate by itself.

· If the music player can be set to exclusive mode, the audio signal will not be resampled by the computer/phone, so the sampling rate of the output signal is the sampling rate of the original file, and the sampling rate displayed by this unit is also the sampling rate of the original file.

· Because some players can't be set to exclusive mode, the audio signal will be resampled by the computer/phone and then output. So this unit will always display the sampling rate set by the computer/phone.

· We recommend using Audirvana player on MAC OS and Foobar on windows OS.

‍

· Incorrect firmware version. Please re-flash the correct firmware.

· If the computer does not recognize the unit, try entering DFU mode by pressing the headphone button on the remote control 5 times while the unit is in standby mode. If this does not work, try using another USB port, another USB cable or even another computer.

‍

· If you accidentally enter DFU mode, unplug and re-plug the power cable and reboot this unit. Try to re-flash the firmware if DFU is still displayed.

‍

· Amplifier circuit may output abnormal DC voltage.

· Please flash the latest firmware first.

· If use the RCA output, please switch the output mode to Line out by doule-pressing the knob.

· After changing the song or turning down the volume, unplug and re-plug the power cable and reboot the unit.

· Disconnect other devices and reboot. If the problem still persists, your unit may be defective. Please contact the store where you purchased it.

‍

· Supply voltage too high/too low. Please use TOPPING’s power adapter.

‍

· DAC abnormal. Try using another DC15V power supply. Disconnect other devices and reboot. If the problem still persists, your unit may be defective. Please contact the store where you purchased it.

‍

· Please check whether it is set to DAC mode in the setup menu.

· In PRE (Pre-amplifier) mode, the this unit will always display the volume level. When the sampling rate of the input signal changes, it will display the sampling rate for 2 seconds and then continue displaying the volume level; In DAC mode, it will always display the sampling rate, keep the maximum volume output and the volume is not adjustable.