Can't be turned on
· Check the power connection.
· Check if the rear panel power switch is in the ON position.
· If the fuse is blown, try using the spare fuse.
· Try with another power cable.
· Try with another power outlet.
No sound
· The device did not power on. Check the power supply.
· Check that the proper input source is selected.
· Check the output setting.
· Check the connections for all devices.
· Insert connection cables all the way in.
· Check the volume of all devices and whether they are muted.
Noisy playback
· Try with other songs.
· Check to see if the problem is with the source, downstream equipment and cables.
One channel with noise/no output
Check to see if the problem is with the source, downstream equipment and cables. You can try swapping the left and right channel connections.
Channel imbalance
Check to see if the problem is with the source, downstream equipment and cables. You can try swapping the left and right channel connections.
Remote control not responding
· Enable remote control function in the setup menu first. [Setup Menu - Advance - Remote]
· Try to insert one CR2032 button cell.
· 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 RC23 remote control can be used to operate either D900 or A900. To switch the device it controls, press and hold both the “Standby” and “Mute” buttons until the indicator light flashes twice.
PN / P voltage abnormal
Negative and positive voltage abnormal. Disconnect other devices and reboot. If the problem still persists, your unit may be defective. Please contact the store where you purchased it.
5V voltage abnormal
Abnormal input voltage. Disconnect other devices and reboot. If the problem still persists, your unit may be defective. Please contact the store where you purchased it.
HP DC abnormal
Amplifier circuit outputs abnormal DC voltage. After changing the song or turning down the volume, unplug and re-plug the power cable and reboot the unit. If the problem still persists after disconnecting the other devices and restarting it, the unit may be defective. Please contact the store where you purchased it.
Pos / Neg Overcurrent
Positive/Negative overcurrent abnormal. After changing the song or turning down the volume, unplug and re-plug the power cable and reboot the unit. If the problem still persists after disconnecting the other devices and restarting it, the unit may be defective. Please contact the store where you purchased it.
DAC Abnormal
Disconnect other devices and reboot. If the problem still persists, your unit may be defective. Please contact the store where you purchased it.
DIR abnormal
Disconnect other devices and reboot. If the problem still persists, your unit may be defective. Please contact the store where you purchased it.
FFT DAC abnormal
Disconnect other devices and reboot. If the problem still persists, your unit may be defective. Please contact the store where you purchased it.
Topping other firmware
Please re-flash the correct firmware.
Unknown file
Please re-flash the correct firmware.
No firmware
Unplug and re-plug the power cable, and then flash the firmware again. Be careful not to disconnect from the computer while flashing the firmware.
Update failed
Please re-flash the firmware.
File size large
Please re-flash the correct firmware. Try to reboot the computer or use another computer.
Firmware damage
Please re-flash the correct firmware.
The usage of the FW port
For firmware upgrade only.
