Reason 6.5 Rewire puts previous tracks out of sync

I just bought and installed Reason 6 and updated to 6.5. I also upgraded Cubase 5 to 6, then the 6.5 download. When I open a Cubase project with previously recorded tracks, select Reason Rewire in the Device menu, open Reason and set up an instrument and go back to Cubase, the previously recorded tracks are way out of sync (like 10 bars out) and play back at a slower speed than normal.This suggests to me a bit rate and/or sample rate issue, but both Cubase and Reason are running in 32-bit mode, 44.1K. Everything is fine with the previously recorded tracks if I close the project without saving and start over. It’s when I load an instrument in Reason that the problem happens. I don’t even get as far as to assign Reason to a MIDI track’s output. If I open Reason but don’t load any instruments, I can go back to Cubase and everything is still intact.

Anyone run into this and have a remedy?