midi synch problems help!!!

I'm new to this forum so bear with me...I've been using my 4000 for about 2 years now and still love it even with it's quirks.. I upgraded to os v1.51 about 4months ago and recently upgraded to 1.6. My new problem is if I make up three sequences on the mpc and synch the machine up to my roland 2480(something Ive always done without issue) when I change sequences manually while the unit is playing it starts the next sequence properly but it will play at double the tempo. I've tried everything I know of to resolve this but I cannot figure it out. It will be random in length meaning that it will play a sequence double time for maybe 2 or maybe 5 passes and then resume normal tempo. I've tried midi clock and mtc at various frame rates all with no luck. Sometimes it even does it in song mode upon the sequence chages. Any help would be greatly worshiped!!!!

who is the master ? MPC or the VS?
If you have the mpc as the master I would try switching the roles between the two

I always run the 2480 as master and use the mpc for drum tracks and samples. So I'll hit play on the 2480, the mpc starts up, everything is normal, then i want to switch to sequence 2 from 1 lets say nd as soon as sequence 2 starts the mpc (only) goes into double time. After 2 or 3 times around on sequence 2 it will snap back down to proper tempo...

Yo, you need to switch back to operating system 1.51, a similar thing happened to me except I use sonar3 instead of a roland 2480. I tried everything and nothing worked, I e-mailed akai and they never e-mailed me back. I had version 1.60 for a long while and syncronization has never been good and I have paying customer's so I went back to 1.51 and now the sync is rock solid like it's suppose to be. I hope the mpc doesn't have this problem in the next update. Peace.

That's kinda what i was thinking but i wanted to be sure there wasn't a new feature i didn't know about that might need to be switched on or off.....Thanks a million man!

planetferg