Intermittent Speaker Crackle Static Like Sound on brand new iMac Pro

I ordered an iMac Pro 8 Core Intel Xeon, 128GB RAM, 1TB, 16GB Raedon Vega 64. When I recieved the iMac Pro I noticed a very faint crackly noise in the speaker almost like a static build up but this went away and I thought nothing more of it. I then decided to install Windows 10 via bootcamp which was a pain to install as is but I pursurviered with it and finally got it to install. I then watched a film through windows 10 and the phantom static speaker crackle returned but with a vengance it was so loud! It was extremly random and the issue would go away when i paused and started playing again. However the imac then started to do it much more frequently on an intermittent basis. Then windows 10 after a specific windows update knocked my bluetooth magic accessories off and I managed to get them back up by connecting a magic trackpad by usb and removing the update. Finally fed up I called apple to which Apple Care fobbed me off constantly saying its a software issue its a driver issue and I kept saying that a crackle of that sort would no way be software and if it was software other people with iMac Pro's would be experiencing the same thing. I then after a few days battling with Apple Care advisors demanded a replacement and they shipped a replacement too me. Recieved the new one and returned the faulty one, ONLY TO FIND THAT THE NEW ONE HAS EXACTLY THE SAME ISSUE! Crackly speakers that are so loud it literally hurts my ears. I have been on the phone to apple all of today and am at a loss they are still saying that its software but I have until monday to request a refund on a 7 grand machine but they have referred it to their software engineering department and a response from them could take 2-3 business days!!!! I am utterly disgusted at apple and I feel they have gone down hill as they did not used to be like this. Is anyone else having these kinds of issue's with their iMac Pro's or is it just me.