I believe it sounded like... extremely high revving. Most of those pertain to issues which invoke slowdown/stop... Uh... So... I'm not sure... *keeps checking them*
Edit: I don't think it was like those. Honestly, my memory easily blurs when it comes to things like this. However, if it sounded like any of these, I'd definitely have emergency shut-down. Trying to recall on my memory, I do believe it was like... revving up FAR higher than I thought was safe. I suppose I expected it to start making any of these sounds, but it didn't. However, the spin up was FAR HEAVIER than any of the drives work. It was highly audible, and sounded dangerous.
And yes, that's odd. A problem where the disc speeds up... I'm hoping maybe the diagnostic did this on purpose, but I can't tell...