Also, the headset's yellow light is on. This was working last time and I haven't changed anything - what could be causing my headset's visuals to be completely blank?
Try covering the sensor beside the yellow light with your finger. Does the light turn off, stay orange, or go white? If it goes off, try booting your computer with your monitor unplugged, then cover the sensor (enter your computer password first if you have one).
If the light now turns white when you cover the sensor, plug your monitor back in and your good to go until your next reboot.