Scrolling issue when using Photoshop

Hi everyone! I draw frequently on my Surface Pro 4 using both a Bamboo Ink and Wacom intuos, and have run into an issue where when drawing, vertical motions with a tablet pen result in scrolling up and down instead of drawing. There's no visible on-screen cursor (no hand icon) and it only happens with photoshop- no issues with paint or SAI or any other drawing program. This occurred after updating my Surface this morning, and it was working with no issue immediately prior to updating. I've tried reinstalling drivers for both the Ink and Intuos, deleting Photoshop and reinstalling from scratch, restarting and updating my computer, all to no avail. Any possible solutions to this issue?

Thank you!