D33ZNUT5

I dont hear any hiss.

acribb

Yes, take out the resistor. That is what is limiting the frequency range. It's right behind the aux input female aux receptacle. Unscrew the ring off the female aux receptacle. Then take the two philips screws out to release the aux connector. Then fish out the cable and there should be a 'lump' a few inches back from the female receptacle. Unwrap the felt tape and you will see the resistor. Cut the connector and then twist the wires back together without the connector. Use 2 mini electrical connectors to twist them up. Then tape them with electrical tape. You will be good to go after that. The sound is rich and full like it should be. I have had this on my 2004 530i for 6 years now with no issues. Search the forum more on this as there may be more detailed instructions.

Disclaimer:: I did this mod on an OEM BMW Aux input that the dealer installed in my glovebox. Make sure you have a resistor before cutting any wires!!

Pianoman26

It's good to hear the AUX works well for some of you, I'm hoping I can fix mine! I realize I have done a poor job of describing the interference. It sounds kind of like a DVD reading data plus continuous electronic higher notes of which the frequency gets higher or lower as the engine revs up or down respectively. The noises can be heard with the audio device playing or paused..

acribb

Directions to remove resistor in aux input-
https://5series.net/forums/topic/23890-aux-cable-mod/

rbcook

Okay, so I went to my car to try it out(I usually take advantage of any reason to go sit in my car). iPhone plugged in listening to music via AUX input, no hiss/interference whatsoever, in play mode or in pause. I'm not an expert, but maybe your dealer is just blowing you off. Make them go listen to the AUX input in another car, and show them that it does NOT have the sound interference problem. Good luck!