I bought two audioquest cables both high quality... One firewire and one usb. I have blind tested this several times... can you tell me why the usb sounds slightly cleaner with a more forward vocal and high end freq? The firewire sounds good also, but a thicker sound with more low end freq.. and maybe more separation... how is is this possible?? Please I need to know which one is the right choice? and is the performance with usb really on par with firewire? I don't care which one it is I just want to use the best one... my computer was built by adk optimized for audio and very powerful... so the computer is not an issue, I just want the truth! why is there a difference?? and which runs better!!