I’ve been recording for several months now and I notice that my current recordings sounds less rich, less warm, and slightly more tinny than they used to. I haven’t changed anything (that I’m aware of, that is).
Much more like the built-in microphone of your laptop?
You can do a scratch test. Start a recording and gently scratch your production microphone and then your laptop microphone. You’ll need to research where your computer microphone is. Mine is on the left side to the left of the SHIFT key.
One of them is going to be super loud and that’s the one you’re recording.
Audacity will default to the built-in if it loses contact with the production microphone for any reason. You unplugged it while Audacity was running or the connection has become loose or damaged.
Audacity > Transport > Rescan Devices.
Click on the microphone pull-down in the menu bar and see how many devices are listed. Your microphone may not listed by name, but it’s pretty safe bet there’s more than one. Try the other one.
I’m guessing about a lot of this, but that’s a common cause for your symptoms.
IMO there is processing on that: the hiss level drops when you are speaking (e.g. between 1 and 4 sec),
as if compression was applied.
If you are using an audio interface, that could have on-board compression.
or the computer could be applying audio enhancements before the sound reaches Audacity.
(e.g. Windows audio enhancements, RealTek, Maxx Audio).