92Troubleshooting (Advanced) SoundNo sound. z Press Fn+F4 or Fn+F6 to cancel mute.z Restart the computer.Distorted sound. z Performing Fn key combinations sometimes causes sound distortion. Stop andrestart playback.Cannot change the volume by press-ing Fn+F5 or Fn+F6.z Activate the Windows sound function. When it is not active, the volume doesnot change even if is displayed.“There was an error updating the reg-istry” appears when Sound Recorderis started.z Sound Recorder is started by a limited account user whose language setting isnot the same as the administrator user who last started Sound Recorder. Thisdoes not affect the operation. KeyboardOnly numbers can be input. z When the indicator is on, the keyboard is in ten-key mode. Press NumLk tocancel.Only capital letters can be input. z When the indicator is on, the keyboard is in Caps Lock mode.Press Caps Lock to cancel.Cannot enter special characters (ß, à,ç, etc.) and symbols.z Use the character map. Click [start] - [All Programs] - [Accessories] - [SystemTools] - [Character Map]. Disc OperationThe CD/DVD drive does not work nor-mally.z Set [Optical Drive] to [Enabled] in the [Advanced] menu of the Setup Utility(Î page 76).z Clean the lens (Î page 20).z Check the disc condition (Î page 21).Cannot play back TV programsrecorded on a commercial DVDrecorder.z Finalize the disc on the DVD recorder when the program was recorded in videomode on DVD-R/RW or in VR mode on DVD-RW.A blue background appears on thescreen when playing an MPEG image.z You opened the CD/DVD drive or removed the MPEG disc while it was operat-ing. Re-insert the MPEG disc and close the CD/DVD drive.The CD/DVD drive vibrates exces-sively or makes noise.z Insert the disc correctly.z Check the disc condition (Î page 21).z When writing to a CD using B’s Recorder, set the writing speed at [8x] or less.