Ok,
I do not own a tyros but on my psr2100 this is what I'd do.
First, turn off the OTS link.
Then you can use the different vari buttons as you want, Without changing voices, with or without the fills. Then change the voices using the ots manually if and when you want.
Would that work for you? If not, explain why and I will try to figure out a different procedure.
Jim

[This message has been edited by OldNewb (edited 07-16-2007).]