I have the ATV gen 1 and haven't heard the gen 2, so take this as you will...
I went from a fiber optic toslink to an inexpensive glass cable and noticed very good changes. Everything was more focused, less blurred. Everything got better, but that was the most obvious to my ears. The cable I bought was the Sonicwave glass cable from Amazon for about $25. Very happy with it.
I also added the Audioquest C7 cable - the cheaper one - and the same gains. Not sure if it reduced jitter by better/cleaner power, but it just sounds better. V
I went from a fiber optic toslink to an inexpensive glass cable and noticed very good changes. Everything was more focused, less blurred. Everything got better, but that was the most obvious to my ears. The cable I bought was the Sonicwave glass cable from Amazon for about $25. Very happy with it.
I also added the Audioquest C7 cable - the cheaper one - and the same gains. Not sure if it reduced jitter by better/cleaner power, but it just sounds better. V