Hummer 2006 H2 - Manual (Page 251)

Radio Reception
You may experience frequency interference and static
during normal radio reception if items such as cellphone
chargers, vehicle convenience accessories, and
external electronic devices are plugged into the
accessory power outlet. If there is interference or static,
unplug the item from the accessory power outlet.
AM
The range for most AM stations is greater than for
FM, especially at night. The longer range can cause
station frequencies to interfere with each other.
For better radio reception, most AM radio stations will
boost the power levels during the day, and then reduce
these levels during the night. Static can also occur
when things like storms and power lines interfere with
radio reception. When this happens, try reducing
the treble on your radio.
FM Stereo
FM stereo will give the best sound, but FM signals will
reach only about 10 to 40 miles (16 to 65 km). Tall
buildings or hills can interfere with FM signals, causing
the sound to fade in and out.
XM™ Satellite Radio Service
XM™ Satellite Radio Service gives digital radio
reception from coast-to-coast in the 48 contiguous
United States, and in Canada (if available). Just as with
FM, tall buildings or hills can interfere with satellite
radio signals, causing the sound to fade in and out. In
addition, traveling or standing under heavy foliage,
bridges, garages, or tunnels may cause loss of the
XM™ signal for a period of time. The radio may display
NO SIGNAL to indicate interference.
Care of the Cassette Tape Player
A tape player that is not cleaned regularly can cause
reduced sound quality, ruined cassettes, or a damaged
mechanism. Cassette tapes should be stored in their
cases away from contaminants, direct sunlight, and
extreme heat. If they are not, they may not operate
properly or may cause failure of the tape player.
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