Tom,
That seems like the correct way to me. Personally, I’d rather have Line Level all the time. You might know this already, but it’s best to add as much gain as possible/needed as early in the signal chain as you can. That gives you the best Signal-to-Noise Ratio.
You might want to check the user manual on a couple of things:
1. Whether the nominal output is actually Mic Level and is having gain applied to it by changing the setting the output to a higher level.
OR
2. Whether the nominal output is Line Level (+4dBu) and is attenuated when setting the output to a lower level.
It may be a combination of the two. Either way, there should be a specification where “unity gain” is at.
My thinking behind this is that you may be attenuating a Line Level signal and then adding gain again, which can lead to a higher noise floor along the signal chain.
Hope that gives you some food for thought. 🙂
Wolf
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