I just listened to both your videos with headphones on and it sounds like a C10.
I can't hear any crickets or squeals or anything other than a normal C10.
Yes, the engine is a bit whiny and that can sound like a chirp at certain speeds.
I think it sounds like a happy cat purring away.
Could it be that all your previous bikes were unfaired?
If you are used to nekkid bikes the quiet behind the C10 fairing (and the fact that the fairing reflects engine noises back to you) makes you hear all kinds of things, especially if she still has the factory mufflers.
With time you'll learn to ignore all the noises, even the camchain rattle, or you will get louder mufflers that drown out the noises.
Then one day the camchain rattle will just stop,.... and you'll
yourself thinking that something is broken.
In fact it will just be the camchain tensioner finally ratcheting forwards one notch.
Go meet up with some other local C10 riders and listen to their bikes. You'll see what I mean.