Thanks for the clarification.
As I said, I have used the same cable, just changing from balanced to unbalanced type.
I think that differences between my results and yours can be re-conducted to the different equipments used during the test. The cable length can also be an explanation. My cables are one meter length.
Well, for me it's a good news, because RCA is cheaper and better.
A very uncommon happening for this hobby :-)