I can actually see where you're coming from, but I disagree.
I really love the soundtracks to all the series, pretty much. I think X had a great soundtrack, but it's my least favourite Final Fantasy game by far just due to the direction of the game itself more than anything else.
I also love a number of tracks in XIII-2 (especially invisible depths, possibly my favourite final boss theme ever) but didn't think too much of the game itself.