It could be the mic, but it also could be several other things.
The compressor may be on if it's just making the noise when you are NOT singing or speaking.
The input level may be too high.
The e.q. on either the overall mixer or on the microphone, or both, may have excessive highs set.
You may have a DSP set on the mic that is not appropriate.
You may have electrical interference from nearby source, such as a fluorescent light or other appliance.
I would reset everything to the factory default settings. It shouldn't be making any noise then. Then, try a different mic.
I suspect it is something other than the mic though.
My 2100 produces crystal clear vocal with no noise at all.
Let us know if any of this helps.
DonM