I had about 50% freezes when hosting this with nginx + php-fpm. Increasing the sleep time seemed to help. I set the "X-Accel-Buffering: no" header with an additional flush(). This effectively disables nginxs fcgi buffer and makes sure headers are send immediately. Success rate is 100% now.
@Xdqwerty, to answer your question, they're a fusion Brit-pop/J-pop/electronic band with a woman vocalist. Flamingo is hands down their best known song but they've got a ton of other really good songs