I have an alpine 9851 cd deck added an aux input for my ipod using an ainet-rca adapter and a monster rca-headphone cable. I can't tell a differtence when music is playing, but when I have no device connected and i have the deck on aux and the volume on, i can hear interference from the headlights, alternator? etc. Is this harmful at all or am i just being paranoid. Is there anything i could shield any of the adapters I have to eliminate this?
Thanks

Also, what size tweeters will fit the stock tweeter mounts in a 96 civic ex?