It hasn't recently tarted being loud, it has always been lile his but I've always felt it's too loud but I've never heard another in-person. I'll post a sound clip tomorrow. It's the Black and Decker RTX, the one with 5 or 6 speed settings. Now, to give you a perspective on how loud it is (all examples are just free running, not actually cutting or drilling anything): It is not as loud as an angle grinder but sounds more aggressive than one. Specially at higher speeds it sounds like it's mad at you and wants to burst out of its shell.
It could be you got one that's off-balance. As long as it has always been loud, you should be fine. I have a Craftsman version that makes a nasty shriek from having 2 more bearings than a dremel.
That's what I'm hoping for. I.e. That "dremels" / rotary tools are usually quieter. After using it for while I no longer worry about it being un-safe. Just irritated by its noise when ramped up from the get go. If that volume turns to be normal, i can get used to it I think It seems to be working fime and everything though. I've even noticed earlier today that when it's actually doing work and you gradually ramp it up it doesn't seem to be hat loud. I think however, that this is just percieved quietness, as it is louder when working and while doing that for a while you get acustomed to the volume, then you stop working to ramp up the speed and it doesn't seem that loud. Also, I checked. It's not RTX something but RT650 with 6 speeds.