May I know which version of Photoshop are you using?
Try unchecking Use Graphics Processor from photoshop's preferences.
I'm running what I believe is the latest version, specifically 20161130.r.29 x64. This has been a problem for many versions, though.
Surprising to me, Use Graphics Processor was already turned off. Should I perhaps try turning it on, instead?
I tried it with Use Graphics Processor turned on and still had the same problem.
Thank you for trying out the steps Matthew, Could you provide some more details about your system specifications?
MacBook Pro (Retina, 15-inch, Mid 2015)
Processor 2.5 GHz Intel Core i7
Memory 16 GB 1600 MHz DDR3
Graphics AMD Radeon R9 M370X 2048 MB
Intel Iris Pro 1536 MB
macOS Sierra Version 10.12.3 (16D32)
Storage APPLE SSD SM0512G
More than 200GB free
Note that everything else is fast, I virtually never get a beachball (exceptions for complex filters on large files). Everything else is very fast.