Vertical evenly spaced lines in scanned images

I have an Epson WF-7710 that produces pixelated vertical lines at even intervals across the image when using the flatbed scanner. I've tried 300 and 600 dpi. Color and grayscale. I've tried the Epson Scan 2 software along with some 3rd party to test (vuescan, PaperScan). I've tried changing every setting in Epson Scan 2. Scanning over network vs USB. No difference. Printer usage history only shows 36 total scans. Scanner glass is clean. Scanning images to tif format. When scanning at 600 dpi, the lines are all ~0.725 inches apart / 435 pixels. FYI I also have an Epson WF-7610 and I've scanned

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