Hi all!

I'm very new at this; I had followed a bunch of setup videos from Joe and Gregor a year ago, got it all set up and everything worked great -except the noise floor was really high when I turned the gain up high enough on my interface to get to around -12db in the DAW. So: I was messing around with the faders in Universal Control to see if that would do anything for the noise, and I hit the "reset" button. Now I can't hear myself through my headphones. *sad trombone*
I can hear YouTube videos in the headphones; I'm getting signal (seeing the green bar dance) in the DAW, in Universal Control, on my interface; and when I hit record on my vocal channel in a new song I can hear my vocals play back in my headphones -but not when I record them. In the start page under Setup where you can see your interface, if I switch it to "Windows Audio" I can hear myself speak into the mic through my headphones, but not when I switch it back to my 1810c. 
I'm thinking its the routing somewhere in the software, but I have no idea where. 
Any thoughts/ tips/ tutorial videos are greatly appreciated!

Thanks in advance,
-Mary

Gear:
I'm using a Studio 1810c, a Samson C01 Studio Condenser mic with XLR on both cable ends. Spankin' new Sennheiser headphones plugged into the headphone jack on the back of the interface. 48v button is engaged, gain/volume knob is up. Studio One v4 is up to date; new firmware is installed etc.