No CPU spikes here with Scaler 3 (Studio One v7 on Windows 10 22H2)
Scaler 3 is not a multi-output VST like EZ3 - so clicking on S1 “output” will get nowhere.
Scaler 3 IS multi-MIDI out - you can assign each track from the Scaler 3 arrange tab to send MIDI out to S1.
See my mini-tutorial (5 posts down) within this thread:
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