Isn't PAL speed-up 4%? Granted, it is perhaps a bit odd to quibble over whether 93% or 96% is better, but I'm not entirely sure myself (which is why I'm asking).
Just out of curiosity, what software did you use?
(by the way, it is also possible that the speech went through noise processing. If a noise pattern is more or less consistent, and there are moments when the noise is isolated without dialogue or anything else, then it is possible to reduce much of the noise. This is at the expense, of course, of reducing overall fidelity...though in all honesty, or perhaps because I've never watched with really loud sound playback, I've never *noticed* the humming)