dDog45 wrote:Sam Spoons wrote:edit:- I've just checked and the 1k ohm resistance in the earth path is within the PSU itself.
When you say PSU are you referring to the 96W Plug or the internals of the computer?
Also, that product you mentioned before.. I will also have at least one jack socket available on the interface but I'm not very confident I entirely understand what you mean in your explanation of connecting it as such? Do you mean that product just gives out a ground and you feed that ground to the interface through a TS cable?
The 'wall wart/line rat' PSU not the computer internals.
You need to somehow make a connection between the earth of the system and the mains earth which your system doesn't have at present. Your old desktop PC will have had a good earth through it's mains lead, your new MBP doesn't and that is what is causing the problems. As James said if you can get a suitable connection between the GroundBox and your mains earth that will work fine, or you could even make your own with a length of wire, a TS jack plug and a 13A plug top (in most cases you could just remove the Line and Neutral pins leaving just the Earth pin in the plug) and use the spare jack socket in your interface.