Elektron Musical Instruments

Hi guys,  I need your help, because I have some synchronization
problems...
I'm using the machinedrum in my studio with other MIDI devices
(Synths, sampler, etc..) and a Mac PowerBook G3 - 500 Mhz (Mac OS
9.2). My MIDI interface is a Motu Midi Express XT (8in-out),the audio
one  is a Motu 828 firewire.
Running Logic PRO 6 as main sequencer and MIDI sync master, I've
figured out that machinedrum, set as external sync, has lots of
problem to remain in time with the master MIDI Clock of Logic. I need
to use few milliseconds of delay to keep the MD in time with Logic.
Otherwhise, setting machinedrum  as master and logic as slave, give
me the same timing problem.
Plese, give me an advise to solve this  problems....or advise me
which is the best syncronization setup in an environment like mine.
Thanks a lot, and sorry for my english.
Sticky