Hello,

I just had an aux input installed in my 2006 525xi by my dealer, and am having an issue with the sound quality; there is very little bass response. In reading through some older posts I am confused as to what is causing this. Some say it's the in-line filter, some say it's due to improper installation, and other's say it's due to improper coding. I'm not sure what the cause is, but what I can/should do to fix it. Any help would be appreciated.


Thanks in advance!

could it be the device you are connecting? Did you try a different one?

Curious about this as well. I've been complaining about weak bass from my sub and it occurs that I'm testing against my iPod. When I'm on a CD or on the radio I don't seem to notice the problem which makes me think I probably have the same problem you do. I have the same "opportunity" when hooking my Droid up.

Edit: Called BMW because they just installed my aux port about 2 weeks ago. My SA asked me to drop the car off on Monday night for someone to look at it. I'll let you know if there is any change to quality after I get it back.

There are not coding options to change anything related to bass and Aux input. The only coding option is "fitted" or "not fitted". The OEM aux cables have inline resistors to help protect the speakers when a device is connected with the volumn set high (crackling). I imagine these resistors are clipping the bass. I would start by removing the resistors. You will have to remove the wood dash trim, pull the CIC/CCC/MASK to expose the aux cable. Look for the bulge (like a snake that swallowed a mouse) in the cable and start dissecting. Remove the resistors, splice the wires back together (color matching) and solder the splices. Not saying this IS the solution, just a suggestion on something to try as there are no "settings" to correct such an issue.

I don't know because I don't have this issue. My AUX input sounds friggin great!!! Though I have to admit I have the BSW speaker upgrade, a noise filter, and an aftermarket woofer and amp in the trunk. The sound is amazing from my iPod :thumbsup: