Epson V800 severe banding even on high-bit scans?!

I've had my V800 for about 8 months now, and it was working perfectly before. I took a 5 month break and started using it again and now all my scans, whether 16-bit grayscale or 48-bit color at 2400dpi, have banding in it (attached).

Does anyone know what could be wrong or how I can fix this?

Edit: Just looked closer and zoomed in onto different photos i've taken, this scanner is banding everything from the midtones to the highlights as well!