I use UMDGen 4 to replace files.

I have 2 iso's GTA VCS and CW. I can replace radio in GTA CW with my selfmade .at3 radios. But this doesn't work for GTA VCS.

I tried to replace files from both games:

CW >> VCS doesn't work
VCS >> CW works
VCS >> VCS works

I suppose there are several .at3 versions. How can I become the proper one for VCS?

PS: I know, that I can RIP my CDs and use them as radio. In my case I want to completely replace all radiostations.