Thanks for sharing everyone this has been a really informative post! It looks like the RJM Music Mini Amp Gizmo is discontinued now! From what I've read the RJM doesn't give you the ground loop and you don't need the Hum Eliminator. Does anyone know if that is true? Is it maybe because it has a power supply and grounds it? I need to get a solution for my set up (Mark V and Helix) but am having difficulty sourcing the Mini Amp gizmo and appears a lot of people have been trying to buy them... not sure why they discontinued it so might have to look at the EM Custom option with the Hum eliminator. I don't really want to use the Hum eliminator because I'm assuming adding one of these devices in will reduce sound quality? Thanks!