can't use spdif out (opt) in old cubase project

i’m using cubase 8. i wanna use spdif out (opt).
so i have changed the mr816 digital setting from adat 1-6 + spdif(coax) to spdif (opt) + spdif (coax).
and that worked well in my windows 7 and cubase 8 NEW PROJECT.

problem is in OLD cubase 8 project.
when i open the old project, and open F4(VST Connection),
I CAN’T get sound because there is only Analog out and ADAT, spdif (coax).

do you understand?
spdif (opt) is activated only NEW PROJECT.

how can i solve this problem?
if you know, please tell me the solution.