16. What should I do if the BTA30 Pro cannot be turned on/cannot be connected/ has no sound?

【Can not be turned on】
The BTA30Pro doesn't have a reset button. If it fails to boot up, please try to re-plug the USB cable or replace the USB cable and restart the BTA30Pro.
【No sound】
RX mode
1. Please make sure the MODE switch is in the BT RX position.
2. Please confirm whether it is in the paused state.
3. Please check that the volume knob is in the proper position.
TX mode
1. Please make sure the MODE switch is in the BT TX position.
2. Please confirm whether the input source is selected correctly, short press the INPUT key to switch the input source.
3. In the “connect to two devices simultaneously” mode, the LDAC and aptX LL codec can’t support simultaneous sound from two devices.
4. If “USB input is connected to the computer, the BTA30Pro Bluetooth transmits to the Bluetooth device, but there is no sound": Windows computer (the computer has recognized the BTA30Pro) you may try to uninstall the drive.
5. Please re-plug the adapter cable, replace the wire for checking whether there is a bad contact.
6. Please short press the LL/HD key to switch the Bluetooth codec. If the codec is not supported by the receiving device, there will be no sound at the receiving device.
7. Only LDAC codec has sound, APTX and other codec have no sound? Please check the settings in FiiO Control to see if output in other formats is enabled.
8. Please check that the volume knob is in the proper position.
DAC mode
1. Please make sure the MODE switch is in the DAC position.
2. Please confirm whether the input source is selected correctly, short press the INPUT key to switch the input source.
3. Please check that the volume knob is in the proper position.
No sound from optical/coaxial output:
1. Please confirm the maximum sampling rate supported by the receiving device. The BTA30Pro coaxial output supports up to PCM384KHz/DOP128, and the optical output supports up to 192KHz. Please check if the track being played exceeds the sample rate supported by the device.
2. Please confirm whether "upsampling" in FiiO Control is turned on. When this switch is turned on, the sound below 192kHz will be output at 192KHz.
3. Please try to switch between different outputs, LO, coaxial, optical, if only one output port has no sound, it means that there is a problem with this port.
How to clear pairing on BTA30 Pro:
After the RX/TX/DAC mode is turned on, press and hold the INPUT+LL/HD keys for about 5s in the non-pairing state.