I seem to have developed a high pitched hum through my aux channel... I hear it at low points in music and between songs. And I don't get it through my CD player, not sure about the radio since I need the volume up and for someone to actually be quiet on the radio!

Anyone else have this issue?

 

Does it happen when nothing Is plugged into the aux? Does it happen when your aux source is paused?

 

It happens with and without something plugged into the aux port. My guess is that something is going on with the port itself, but have no clue what. Or how to fix it...

 

Albie,

I have the same problem at times but not all the time. It showed up only after I installed my Alpine amp. If I set everything back to factory it goes away completely and does not come back.

From research i have done while mine is doing it, it seems to be a grounding problem but not one that I have been able to reproduce consistently.

 

I would think that if it were related to the new amp, that I would hear it with any input. I don't hear it with the radio or the CD - just the aux. And my hum is only noticeable when the volume is up past half way and it is there all the time. When Kevin had the car last week, he didn't have time to look at the port itself, but he also thinks it's a grounding issue in the port.

 

A grounding issue in the port itself would make sense if it is there all the time and only on the AUX. The wires there are very thin and could easily break or the connector is not seated tightly to the port itself.

 

Bingo, it is a ground problem, but not much you can do to fix it. I fixed it slightly in my wifes '05 MCS with a Memphis Audio Amp by turning the gain down on the amp and the line level output converter. I know I have a great ground, but something with the way these little cars engines wind up when you hit the gas always causes stereo noise. Pretty weird, but yes it is a ground issue. And I am not so sure there is anything you can do to totally FIX it, you can simply dampen it.

 

i had the problem too with iphone 4. it doesn't happen with all devices. i think it's something about the jack on the iphone 4. what caused it for you?

 

Spoke extensively with Kevin about this issue on Friday since he had my car last week to do some testing for the Soundstage Upgrade. While we were hoping that it was simple grounding problem in the Aux jack, his testing indicates that the issue is likely in the circuitry in the head unit. There is no hum at all when using a CD so it is related only to the Aux function and Kevin has seen it in a number of R56 MINIS that he has had in the shop over the past several months.

After talking about the options (there are really none that Kevin can offer) we both felt that MINI needs to take a look at mine and I will be bringing it in under warranty to see what they can do. The bottom line is that there is something very wrong with the Aux and it is in more than one car that Kevin has seen. I've got 10,000 miles left on my warranty... I'm going to give it a shot.

If you have this issue and you're under warranty, I think it's worth it for you. And it may be a better situation for all of us in the long run if MINI is getting this problem reported repeatedly. Kevin also felt that since the problem seems to be so widespread, MINI may have already come up with a fix.

If my dealership balks, is there a problem trying to go to another dealership?

 

what device are you using?

 

An iTouch. But that isn't the issue - it hums with nothing plugged into the Aux. It is a hum that increases with volume so if something is turned up, I hear it only between between songs. If I'm listening to music at a moderate to low level, I can't really hear it at all.

Try it in yours when you get a chance - have nothing plugged into the Aux and just turn your volume all the way up. It will be very obvious (if it is actually there like it is in mine).

 

Here is the nearfield measurement of the AUX noise from Albiecrazy's MINI. The blue is the door woofer, the green is the midrange, and the red is the tweeter. The grey is the background noise - hard to see, but basically you can ignore everything but the peaks at 2k and above.

You can clearly see the noise at 2k, all the way out to the 8th harmonic. I haven't put the question to our engineers yet, and at this point I don't know the cause. I can confirm that I've encountered it in other R56's, but unfortunately I didn't measure them for comparison.

 

Albie, I don't remeber all the options you have installed in your car like Bluetooth etc. can you get back to me with the list. Depending on options the aux signal is routed differently to the head unit i believe.

May we can eliminate a module here and there to see if any of those are causing the problem.

 

Sorry, Eric - hadn't been back here, but I do have an update. But first, I don't have any bluetooth options in my MINI...

Took it into my dealership - they understand that Kevin has installed the Soundstage upgrade, sub and amp. First step was to replace the Aux jack. That didn't solve it.

Next step is to pursue it with MINIUSA. I know it isn't just my car. My SA went out to his 2011 S and it has it, too. Mine is more pronounced now since I have 500 watts amplifying it, but I can bet that 3 out 10 MINIS on this board have this issue. Here's how you check:

Switch input to Aux.
Turn the volume all the way up with nothing plugged in.

If you hear a whine that gets louder as you turn it up, please post here. I may even start a more prominent thread. I really want MINI to do the right thing and if it's as common as I think (and Kevin from Integral Audio) MINI really needs to look into what's going on with their head units.

 

Schatzy,

You're the resident expert on all things MINI circuitry related - would love to get your latest thoughts on this. I suspect either an engineering and/or a QC issue with either the headunit PCB or, more likely, one of the PCB mounted components that handles the AUX. It definitely is NOT in the input or output stage of the HU, or it would be present on other sources. I feel confident that has to be AUX specific, even if it is something else causing noise on the AUX circuitry.

Walter,

Forgot to mention this, but I would suggest to Matt that he try unplugging the AUX jack plug from the back of the HU and seeing if the noise is still present. I don't think it will be, but if it is the jack itself and 30+% are bad....

 

Matt did replace the jack, but I'm not sure if he ever disconnected it from the HU. When the rep from MINIUSA comes out to inspect it, I'll bring it up with him/her.

 

Final update: MINIUSA did not get involved other than to tell the dealership to replace the head unit. And that did the trick - no more hum. Double checked the tuner and CD and they are clean, too. Very happy.

Certainly, this hum would be difficult to hear in a stock MINI without amplification. But if you have a Gen 2 and it's still under warranty (< 50,000 miles) I would look into it soon. Taking apart the entire dash involves a lot of labor...