Monitors are never exactly the same. When I'm at work, sometimes an image will look blue on one monitor, I pass it to another monitor and now it looks purple. I think there are a few different things that could be happening. You might need to adjust your monitor settings, but be careful when doing so. I used a color calibration on my laptop a long time ago for work and it completely messed it up. Like white became dark grey kind of messed up. The IT guy didn't know how to revert it back and messed up the colors. I finally found how to revert the colors back but it still acts weird. When I start up my laptop, it displays the wrong colors first and after a few minutes goes back to the original, correct color settings.
Sometimes images, especially with effect layers, don't save properly. I love to use the different layer styles and I noticed once that no matter what I did, the image became saturated after uploading it online. I even took a screenshot of the image and it still didn't upload correctly. I haven't run into it recently, but it was so weird.
Try adjusting the contrast of the image and tilting your screen. There may be some artifacts there that you can't see when viewing normally.
Another trick that I do... I haven't tried doing it in CSP, only Photoshop... but to find artifacts, I add a stroke layer style to the image since it will add a stroke around everything, even if it's 1% opacity. Of course, to do this the layers would need to be transparent somewhat. But there might be something there somewhere.