[fluid-dev] slow direct midi playback

[Menteco]

Hi, I've solved the sound artifacts problem(1), but there's one issue left:
if I play a MIDI file this way...
fluidsynth -m alsa_seq 8MBGMSFX.SF2 celebrat_d.mid
...the playback is steady but slow.
on the other hand, if I play it this way...
fluidsynth -m alsa_seq 8MBGMSFX.SF2
MIDI file plays with KMid through fluidsynth
...playback is the right tempo.
What could it be the cause of that playback lag?

Cheers,
Paul www.menteco.tk

(1) I have:
a. recompiled the kernel 2.4.22 with ALSA, capabilities and Andrews' low 
latency patch
b. set the IRQ priority of my soundcard higher than that of my videocard
c. and made fluidsynth suid root.