Audio Systems: Auto stereo system, radio interference, audio reception

Question
QUESTION: I have an '03 Buick Lesabre and in the last two weeks, my reception is terrible, both AM and FM.  Everything else appears fine, such as CD and cassette.  Any suggestions.
ANSWER: have you had anything done to engine in last 2 weeks? sounds like bad/improper spark plugs/wires...

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QUESTION: What do spar plugs have to do with audio reception?  I have not had any work done that would involve the spark plugs.

Answer
plugs generate noise if they're the wrong type. since you haven't had any work done, i suspect plug wires even more. plug wire deteriorate over time and can cause radio interference, and intermittent engine 'missing' at different operating conditions. with plug wires going bad, it makes the noise 'floor' much higher, making radio agc circuits kick in, meaning you can only receive the strongest stations.