I don't think I've ever had an experience on Gringotts where there was one effect that put into the category of a "bad" ride. I feel that must be due to luck. The most major issues I've had on the ride have had to due with water/heat effects and those have steadily improved every time I've gone. I'm very glad I haven't had issues with the music, as it is in my opinion, one of the most stunning aspects of the ride. With the quick, energetic start, and the grand, almost emotional finale, I'm always breathless when I exit the ride and a good part of that is the enveloping music immersing me into the ride. I hope the issues that occur are fixed as that would really change the ride experience for me and I'm sure many others.