I hope someone can help me. I am using Digital performer and a JV-2080. I will play a kick track, hihat track and a boucning string line. The music is very spastic. It is not locking into the rhythm. I looked at my MIDI interface, Sequencer and at the JV-2080.I cant get the musikc to stop being erratic. Can some one relate or has a solution. Please let me know

Are you using pitch bend or aftertouch? (You might be using aftertouch accidentally if you didn't turn it off.) If you have a lot of that information going across the MIDI wire, it will mess up the timing. Your sequencer should provide a way to thin or erase the control messages you don't need.

Are you using a Mac? Sometimes, the PatchBay program seems to lose the connection between timer ports. (There needs to be a connection between the hardware and the sequencer.) You just need to redraw it.

I know a guy who owns a JV-2080 expanded with a Hip Hop board. When he plays sequences on it with any other instruments than drums,it sounds OK. But when he uses drums + other instruments, it happens exactly the same thing you describe.
If he tries the same sequence on a JV-1080 - it works fine.
I don't know what it is but after reading some mails on the problem there is the possibility that the JV-2080 is even slower than the JV-1080 on account of the amount of information it has to handle.
Could it be because of the expansion board!?
Do you have an exp.-board in it?