induction

[Karl Robrock <robrock@domain.elided>]

My 164 stock infinity stereo has the following problem: when the volume is
high and there is not much music playing the engine humm can be heard
through the speakers. I assume this is by induction from the spark plug
cables or some such nonsense. It is quite annoying to hear the engine rev
through the speakers. THe pitch is much higher than the engine rpms (I
think). It sounds quite ridiculous when I drive aggressively because you
hear this little whine proportional to engine speed and it makes the
engine sound pathetic. 

anyone have this problem? know solutions? I heard that the cover on the
distributor cap is supposed to shield magnetic fields, but it is plastic,
o I don;t know how it could do that too well.

thanks

karl
'91 164L

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