Cold boot or restart doesn’t seem to make a difference in behavior.
To summarize my experiments so far:
| Device | usb3 on boot | usb3 post boot | usb 2 on boot | usb2 post boot |
|---|---|---|---|---|
| ssd via powered sata to usb adapter |  |
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| keyboard | |
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| flashdrive | |
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| osmc store powered usb hub without any device connected | |
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| above devices connected to that hub | |
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