Weird speaker interference

[Brew]

While driving down the A2 earlier heard a strange crackling noise coming from the rear, originally thought it was my laptop in the boot so pulled over but it was coming from rear driver side speaker. Got louder and louder then the other rear speaker started. Turned the engine off but still continued. Carried on with journey and then front speakers started - so all 4 really really loud, like some kind of interference but could not be controlled by the volume or through the I-drive. This went on for 10-15 mins but as soon as I pulled of the A2 it stopped. All now seems ok and no damage to speakers.

Any ideas? Could it have been some sort of a frequency jammer do you think??

Edited by Brew on Wednesday 30th January 21:11

[Brew]

Thank you very much for posting - that sounds exactly the problem. I'll contact my dealer straight away.