COMPRESSED AUDIO FILES
(MP3/WMA/AAC)
Explanation of terms
.MP3 — MP3 is short for Moving Pictures
Experts Group Audio Layer 3. MP3 is the
most well known compressed digital
audio file format. This format allows for
near “CD quality” sound, but at a fraction
of the size of normal audio files. MP3
conversion of an audio track can reduce
the file size by approximately a 10:1 ratio
(Sampling: 44.1 kHz, Bit rate: 128 kbps)
with virtually no perceptible loss in
quality. The compression reduces certain
parts of sound that seem inaudible to
most people.
. WMA — Windows Media Audio (WMA)
is a compressed audio format created by
Microsoft as an alternative to MP3. The
WMA codec offers greater file compres-
sion than the MP3 codec, enabling
storage of more digital audio tracks in
the same amount of space when com-
pared to MP3s at the same level of
quality.
This product is protected by certain
intellectual property rights of Microsoft
Corporation and third parties. Use or distribution of such technology outside
of this product is prohibited without a
license from Microsoft or an authorized
Microsoft subsidiary and third parties.
. Bit rate — Bit rate denotes the number of
bits per second used by a digital music
file. The size and quality of a compressed
digital audio file is determined by the bit
rate used when encoding the file.
. Sampling frequency — Sampling fre-
quency is the rate at which the samples
of a signal are converted from analog to
digital (A/D conversion) per second.
. Multisession — Multisession is one of the
methods for writing data to media.
Writing data once to the media is called
a single session, and writing more than
once is called a multisession.
. ID3/WMA Tag — The ID3/WMA tag is
the part of the encoded MP3 or WMA
file that contains information about the
digital music file such as song title, artist,
album title, encoding bit rate, track time
duration, etc. ID3 tag information is
displayed on the Album/Artist/Track
title line on the display.
* Windows® and Windows Media® are
registered trademarks or trademarks of Microsoft Corporation in the United States
of America and/or other countries.
Playback order
.
The folder names of folders not contain-
ing compressed audio files are not shown
in the display.
4. Audio system
4-7
COMPACT DISC (CD) PLAYER
SymptomPossible cause Possible solution
Music cannot be played back. The disc is inserted upside down.Insert a CD with the label side facing up.
Moisture condensation occurs inside the unit. Wait until the moisture evaporates (approxi- mately 1 hour).
The cabin temperature is too high. Wait until the cabin temperature becomes
moderate.
The disc is scratched or dirty. A disc is not
always playable if it is scratched. Wipe off any dirt from the disc.
Depending on the condition in which they are
stored, discs may become unreadable due to
deterioration (for example, keeping the discs in
the passenger compartment, etc.). Change the disc with a deterioration-free disc.
Do not use a deteriorated disc. The label surface
of the disc may crack or chip, and the layer of the
label surface may eventually peel off.
The compressed audio files cannot be played
back. If both music CD files (CD-DA data) and
compressed audio files (MP3 data, etc.) are
mixed on one disc, the audio compression files
cannot be played back.Prepare a disc that includes compressed audio
files only.
The files are not named using characters that
are compliant with the specifications. Use the character codes and the number of
characters that are compliant with the specifi-
cations for folder names and file names. In
addition, always use “.MP3”, “.WMA”, “.mp3” or
“.wma” for file extensions.
It takes a long time before the music starts
playing. The disc contains a large amount of data. Some time may be required to check the files. It
is recommended that unnecessary folders or any
files other than compressed audio files should
not be recorded in a disc.
The sound quality is poor. The disc is dirty.Wipe off any dirt from the disc.
11. Troubleshooting guide
11-7
