Three main factors can cause this and there are three possible countermeasures.
■When the Windows built-in sound device setting is the cause
Refer to case 4 in the troubleshooting guide [here].
■When the connection or other equipment is the cause
An unstable connection with your PC/Mac may cause this problem.
To solve this, shut down your PC/Mac and disconnect all other USB devices and USB hubs.
Then, connect the unit directly to a different USB port.
■When your system (PC/Mac) is the cause
The following may solve the issue:
- Quit all other applications
- Disconnect from the internet and exit security software
- Turn off wireless connections such as Wi-Fi or Bluetooth
- Turn off power-saving settings
If your computer's system doesn’t meet the requirements of rekordbox, it may cause the issue.
Read details on system requirements [here].