Sizzling sound from Bose on the highway

[Standspurpirat45268]

Hello everyone and I'm sorry for writing in English.

I do speak some German but it will be a lot easier for me in English.

I'm brand new Insignia Sport Tourer owner and I'm very happy with it. It has BOSE Sound System. To be honest, I had Audi A6 1996y with Bose and it was a lot better than this in the Opel - it was more richer, warm and room filling.

Anyways - I have this problem with the Insignia.

When travelling with higher speed (>110km/h) a noise(sizzle) starts coming from the front door speakers. It can be heard ever with the music off. It is not the I can hear it but when the music plays it alters the sound and makes it really bad.

I tried switching almost everything which made sense but no-go - as soon as I pass 110km/h the noise starts - and it gets louder with the speed.

Anyone has any idea?

Thanks again for the understanding and the English language!

[brausebruno]

Hello

Is this "behavior" only for radio reception or also for a different music source ?

Which system is installed with you (year of your vehicle)?

CD800 / DVD 900 / Navi IL900?

[Standspurpirat45268]

Thank you for your answer!

The noise can be heard regardless of the music source - CD and Radio. Haven't tried Bluetooth streaming and USB.

It is strange that it can be heard also when the sound is muted.

I thought that it was coming from any of the systems - the noise is like a persistent voice service waiting to play a sound. And I can hear it only after 110km/h as it get sort of auto volume.

But I turned every possible feature but the sound is still there. The car is brand new, my guess it was produced 2-3 months ago. It has IL900 (I have Projection, but no OnStar).

[WolfgangN-63]

Your Insignia offers a lot of sounds using the speakers for your radio, e.g. "click" for direction indicators, "beeps" for park distance control units or other alarms.

Perhaps a sound generator doesn't mute properly.

What does your dealer say? Are any errors logged?

Sorry for my bad English ...

[Standspurpirat45268]

The problem is not that the sound can be heard when muted but while the music plays. After 140km/h it even distorts the music sound.

I will take the car to the dealer at the end of the week. I wanted to check first with other Insignia owners because it can turn out to be something common. Maybe it is uncommon feature that is causing it and it can be turned off.

Even with the Auto-Volume set to high the noise is still crearly heard.

And it also bothers me that this problem would not be easy to diagnose ... I can imagine that the dealer can end up dissembling parts (the dash, the doors) and this never ends with happy ending

[BlackTM]

Based on your descriptions i´d suggest that the amplifier has an electrical issue, as all audio is routed from the headunit to the rear of the vehicle to the amplifier. Depending on engine type (turbocharged gas engines) and body the amplifier sits next to a fuel pump controller on the right side of the trunk, which does generate a speed dependent power output to the fuel pump itself. There are other speed dependent signals in the vehicle that might cause similar problems, but they are not spatially close to the audio signal lines.

If wire insulation was an issue and audio lines are in contact with fuel pump lines this might be the source of your distortion. Should easily be located and fixed. Another point to check would be ground connection of both parts. Maybe added shielding might help, but in theory shouldn´t make a difference, as only very few drivers report such a problem, i.e. the quality of the wiring and therefore signal is sufficient for the whole series.

Other issues might be a dying generator or poor power supply towards the rear of the vehicle. If improving ground by drawing an improvised connection helps, that might be an issue. Also check connections to the rear fuse box on the left side of the trunk.

wbr BlackTM

P.S.: just to get it right: are we talking about a right hand or a left hand steering column car?

[Standspurpirat45268]

BlackTM, thank you for the comprehensive analysis. This seems quite possible - given the fact how "thrown" everything look in the back. The car is 2.0 CDTI, 170ps - I'm not technically knowledgeable but it seems like something like that.

Another thing I have in mind is ... the wind. I don't really know how exactly should this interfere but if something is not well isolated ... I'm guessing here.

I did another test today and it is still there. For sure I can hear it from my side. Unfortunately my wife is not "certain" if she hears it from the passenger seat. I'll do another test tomorrow with my father and on Friday I'll take it to the dealer.

Again thank you all for the help and attention

[BlackTM]

In a 2.0 CDTI there is no such fuel pump controller next to the amp. There are other modules like the urea controller, but its wiring is located elsewhere. In a right hand steering column vehicle (given it is one) the A-Pillar connector that includes amplifier wiring shares more lines with other functions, that would be the next thing to check.

Having such distortions just on one input or output sounds rather assuring to me as a wiring issue, as the channels are usually separately wired and only mixed in the headunit or amplifier. Signal noise that affects all channels is either affecting all wiring (i.e. a shortcut to the source of the noise), but then the signal is usually mono too and left/right front/rear volume levels could not be controlled adequate (it might help to find the issue by checking if this noise changes position as those settings are changed), OR it happens within those modules, but they are usually shielded from external RF.

Problems with the latter would require a replacement, a design flaw however would concern a lot more customers than it seems to be the case. OTOH this forum is german language area based, so some build differences and therefore issues won´t surface here.

wbr, BlackTM

[Zapfer06]

Respekt Jungs.

Mir wird gerade klar das ich wieder mal Englisch pauken muss.

Echt Klasse !

So Long

Der Zapfer

[Standspurpirat45268]

So, a quick update a month later ... I went to the dealer and we took the car for a spin. Unfortunately the guy wasn't able to hear the sound and honestly I wasn't quite sure I was hearing it so I nothing really happened.

However around the Christmas days I got to travel a bit more and I discovered the following - it is not the crosswind which is causing the sizzling sound but it is the sidewind. It was quite windy one of the days and on the highway the sound was matching the side gusts. The stronger the wind the clearer the sound was.

So after that I did some looking around and I found that the plastic outside of the side mirror had a gap between the chrome strip. I haven't had the chance to take it to the dealer but I'm pretty sure that this will turn out to be the issue. Also before that I'll cover it with something and do another test.

I have attached a picture for a reference. If anyone can check and confirm he does not have this gap, will be great

http://i65.tinypic.com/2efn58m.png