Casette Adapter, cleaning?

I have a U2 Ipod for my car and have tried several FM tuner devices but they all seem to have static. So bought a cassette adapter and it works fine, except that i have to turn the sound up a little high so i hear white noise from my speakers. is there anything i can do like get a cassette player cleaner since the car is 9 yrs old?
Does the Itrip work well? aka no static and good quality?

itrip wont be better than other fm transmitters you have. did you try turning up the volume on the ipod?

i don't think a dirty head would make the volume lower, just worse quality.