@Another User said:
...are you working coupled?
I tried it both ways. No difference.
Also, the saving of the project under a new name only restores the audio if you revert to the previous state (e.g., delete the plugin you added). So, it's not really a workaround, after all.
Also, UPDATE: I tried creating a server instance for each of the 24 stereo channels and that didn't work, either. It seemed to solve the cutting out of audio, thing, but was completely out of sync.
At this point, I'm just going to use VEP as it was mainly intended: to offload virtual instruments. Which I still have an interest in doing.
As for my need to output the 24 stereo stems for further processing, and back? I still need to find a solution for doing that while we wait for VSL to deliver their "FX Rack" solution for this.
Since my i7 4770K is already water-cooled and overclocked, I'd need to move into a more expensive processor with more cores to do what I need all in one computer. This may turn out to be a cheaper solution than two 48 channel audio interfaces. Well, for sure it would.
Then, I can move my current motherboard/CPU into a slave for other VEP tasks. This is probably what I'll do. Worst case scenario: The faster, higher core CPU is still not enough. In that case, I'll need to go the Audio Interface route and now just have a faster computer and a very fast slave. So, not a total loss, as I've just future-proofed myself a bit earlier than I need to. 😊
But the VEP "FX Rack" solution will always remain the best way, as it allows the DAW to contain all the parameters within its project. Anything else is a less than ideal solution.