You can either manually start the white noise sound in the Fullpower® Sleep app, or have it automatically play (and automatically stop) after a manual sleep recording has been started. With the Fullpower® Sleep system, you have the ability to manually start and stop your sleep recordings for greater sleep analysis control. If you manually start a sleep recording, this will override the auto-sleep recording feature (Menu > Automatic Sleep Recording) for the time the manual sleep recording is active. Your sleep report will start and end at the time you start/stop the sleep recording in the app.
To manually record your sleep, select the Menu > Record Sleep > Record My Sleep Now (towards the bottom right). Be sure to return to the app and press Done Sleeping to stop your manual recording after you wake up.
If you'll be manually recording sleep and if you want the White Noise feature to automatically start/stop, then select Menu > White Noise > ensure you have a white noise sound selected > toggle ON "Play automatically after starting a sleep recording", then choose how you want the White Noise feature to stop under "Choose duration mode", and then tap the back arrow to save your changes.
If you do not want to manually start/stop your sleep recordings, then you will have to go to the White Noise screen and manually start/stop the white noise.
In order to have a sound play, you will first have to have a white noise selected (under "Select a sound"). Afterward, once you tap the play button, you should hear the white noise play either from your mobile device's speakers or from any external device you have connected (e.g. via USB, aux cable, or Bluetooth). If you don't hear the sound, make sure your mobile device's and/or external device's volume is turned up.
Note: For Android users running Android 12 or earlier, make sure to turn off the Battery Optimization features for the Fullpower® Sleep app, in order for the White Noise to work properly. Locate the Fullpower® Sleep app in the app launcher or on your home screen > tap and hold on the app icon > select the info button > tap Battery > change the setting to Unrestricted background battery usage.