See also:

FM
FM signals only reach about 16 to 65 km (10 to 40 mi). Although the radio has a built-in electronic circuit that automatically works to reduce interference, some static can occur, especially ...

Chemical Paint Spotting
Airborne pollutants can fall upon and attack painted vehicle surfaces causing blotchy, ring-shaped discolorations, and small, irregular dark spots etched into the paint surface. ...

Speaker Covers
Vacuum around a speaker cover gently, so that the speaker will not be damaged. Clean spots with just water and mild soap. ...