As the particles traverse the Belle II detector, a sound accompanies each hit in the sensitive ("information-recording") elements. There is a different sound for each detector type (PXD, SVD, CDC, iTOP, ARICH, ECL, BKLM, EKLM).
Use the in-game main menu to control the sound master volume.
If you use an Xbox controller, you may now rotate your orientation in 3D using the right joystick while pressing either bumper. (As before, you may rotate in the horizontal plane with or without the bumper press.)