See also:

Tone control
You can alter various tone settings, e.g. treble and bass or the speed-dependent volume increase. The tone settings are applied to all audio sources. The settings are stored for the remote control ...

Screw thread
Push out the cover by pressing on the top edge. ...

Multi-channel playback, surround
Choose between stereo and multi-channel playback, surround. Setting multi-channel playback, surround 1. "CD/Multimedia", "Radio" or "Settings". 2. "Tone" ...