Group routing reloading issue

I have a recurring issue with my group routing reload.
let´s say I create a stereo buss for the drum overheads, assign the overheads to the group, everything works fine.
I close the project.
When I reopen it, everyting seems routed as I saved previously it but if I Solo the group buss there´s no sound so I have to reasign the overhead channels to the buss to have any sound coming through. After that, no problem until I save -close - reopen again.

Is this a Known bug or is there something i´m missing? I have been working on sx3 for 10 years and this never happened…


And maybe you might be so generous to let us know what you work on now…?

Aw , excuse me…
Cubase 9.5 pro.