Hyundai Elantra N Owner's Manual page 239

Convenience Features
FM radio station
FM broadcasts are transmitted at high
frequencies and do not bend to follow
broadcasts generally begin to fade at
short distances from the station. Also, FM
signals are easily affected by buildings,
mountains, or other obstructions.
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These can result in certain listening
conditions which might lead you to
believe a problem exists with your radio.
The following conditions are normal and
do not indicate radio trouble :
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Fading as your vehicle moves away
from the radio station, the signal will
weaken and sound will begin to fade.
When this occurs, we suggest that you
select another stronger station.
Flutter/Static Weak FM signals or
large obstructions between the
transmitter and your radio can disturb
the signal causing static or fluttering
noises to occur. Reducing the treble
level may lessen this effect until the
disturbance clears.
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