[PD] -alsa -audiobuf ??

[d]

hi list!
i use a dell-laptop with builtin maestro3 soundcard and pd (35test11)
with alsa (0.9beta12).
when i start pd with "-alsa -audiobuf 50" , cpu-load goes to 100% after
a while.
when i use just -alsa (no audiobufsize) pd works forever.
is it generally a bad idea to mix the two commandline switches or is
this a bug?
[same result with other pd and alsa0.9 versions]

thanks for hints
regards
d13b