Slave MPC 5000 to PT9.06 via Beat Clock - timing drifts when

Dear all,

I am having an issue with sync'ing the MPC5000 OS2.0 to Pro Tools 9.06

Have followed the instructions on avid/akai website, the sync works and by adjusting the offset by 2700 samples I can a close to perfect sync.

Issue is the following: I have a selection, lets say 4 bars, looped in Pro Tools. The first rounds, loop, the timing is spot on, as soon as the 3rd round of the looping cycle starts the timing falls out, then on the 4th it locks back into sync.

Hope somone can point me to a fix for this: please do not that MTC synch is not an option as it requires as it requires a bar or two to establish sync. Not apporpirate in my setup..

Thanks,

H.