Weird Noise

Hi all I hope you can help. I recently noticed a weird noise inside the cabin of my SEAL U Dmi!! I'm not even 100% sure where the noise is coming from. It's not a squeak or a banging noise, maybe it sounds almost like"static electricity". Or that something electrical is shorting out!! I think it's coming from the top dashboard area but not 100% certain. I've tried turning off the HUD, opening sunroof, opening sunshade, checking the glove box, the door pockets, boot space, parcel shelf...everything I can think of. I still hear it but only when the radio/music is off as its so quiet. But it's beginning to drive me bonkers. If anybody can help I'd very much appreciate it. Cheers