So I completed all of the Xylophone Tower (with two bosses I’d already beaten, again – that didn’t bode well), and opened up Noise Dunes. That led me to another tower, which appears to contain more bosses.
Bosses I’ve beaten before. Again. Which means that Eternal Sonata has a SuckySuck(TM) bit. darthvadernooooooooooo.jpg
And then, to make things even worse, once I’d killed a boss and was mere millimetres from a save point, the game crashed again. I’d forgotten to clear the cache (which I have to do all the time now, or it crashes). Bah. So I had to kill the boss again.