I agree with what @Madmatt30 said. The only reason that we've moved forward from RCA's is pretty much to make the analogue part cleaner.
If you're searching for a difference, you should check out balanced connections. These could be just normal AUX cables, but the difference is there's a ground lead in each cable. The most common balanced is probably the 4-pin XLR connection (You've probably seen these used with microphones).
I do believe there is a noticeable difference from unbalanced to balanced, but this is once again a subject that can be discussed since it's so subjective in nature.
The balanced connections is WAAAY more expensive, so unless you really want to get a "better" listening experience, you should just stay with normal unbalanced.
The only reason to use a balanced connection is with a fully balanced amp and DAC. Otherwise it's just a connection. A Schiit Jotunheim with a balanced DAC at $500 is as cheap as I've seen for a truly balanced setup. Then you can even spend a couple of hundred bucks on cables.