So I'm sure its been discussed but I didn't realize how low the aux sounds, I have to crank up my volume so high to enjoy it if I pause the music I hear that radio white noise coming thru. I'm really disappointed about this, on my ipod im using the line out not headphone jack but it barely makes a difference. I read a forum talking about getting mp3gain and normalizing all my mp3s to 92db which is cd quality default most of my music was already at that level or louder. I also read else where some other bmws have the ability to raise the gain on the aux input I checked my radio setting but i don't think i can do it. I seems like bmw is trying to "protect us " from ruining our speakers or radio but adding resistors to the line and on top of that providing a really sucky gain. So I'm wonder if anyone here has tried to do something about this.... I don't want to lower my volume everytime i switch sources Ive been thinking about adding something like this to the mix i don't know if anyone has tried it or can tell me what they think about this option.

Its a Adjustable Pre-Amp Line Driver

 

which aux jack do you have?

 

I don't have any proof one way or the other, but I use an old iPhone 3g as an iPod which hasn't been updated in a couple years. When playing the same mp3 file on an updated 4g, the volume is lower when connecting through the bottom. I haven't installed an Aux yet so am only using an FM transmitter which connects and charges the apple products.