Low frequency drone at very low speed
 

Loaded up the car for a holiday and when leaving home, as I slowed down at my gate (rural property) I had this really loud, low frequency drone (no vibration) and I put it down to possibly dust on the brakes. It then happened several times on our trip. Similar situation each time in that I was slowing down (less than 10kph) and the road surface was quite rough, first time was on gravel. So at this stage I put it down to the new AT tyres I just had fitted, but wasn't convinced.

Stopped for some lunch, went to reverse and stopped again for traffic and the noise came back and lasted for a bit after I stopped. So clearly it wasn't tyres or suspension related as I wasn't moving. So now I'm thinking some sort of drive line issue but the lack of vibration puzzled me.

Got to our location, unloaded the car and had no more issues. Loaded up the car to come home and the issue returned. So was it a suspension issue with all the extra weight in the back? Nope. The cause - active noise cancelling!!

We had the back of the car fully loaded up to the roof and this was partially blocking the internal microphones. The noise comes from the subwoofer and at times it was so loud and at such a low frequency it hurt your ears, it was that bad.

Interestingly this has only started with the new AT tyres as we have done similar trips in the past (with the car loaded the same) but with HT tyres. Research tells me there is no way to turn off the active noise cancelling without causing other issues.

I think I read somewhere quite a while ago that sport mode cancels ANC.
My poverty pack doesn't have it so I can't test.
Mb try and see what happens...
John

Poverty Pack here, another reason I like it I think.............

Well done on discovering what the issue was caused by, its always good to figure it out yourself I find........ amazing stuff ....

Poverty packs are the best! less to go wrong.
Just look at some of the Chinese junk. More bling than you can poke a stick at. No chance of getting much of it fixed when it goes bad!

Just a process of elimination and logical thinking (well I’ll claim that anyway :D )

Didn’t even know the car had active noise cancelling until I started problem solving.