Situation:

I have a MacBook pro MacBook Pro (Retina, 15-inch, Mid 2014)

And have 2 External Monitors ASUS VS247 Display connected via thunderbolt.

On each monitor, I have multiple Desktops/Spaces open.

Problem:

When I wake my mac from sleep, sometimes, it switches the recognition of the monitors and all the Desktops/Spaces from Monitor2 are now on Monitor3 and all Desktops/Spaces from Monitor3 are on Monitor2.

The main monitor (the one on the laptop) always stays the same.

This happens on an average once every month. I was unable to find a specific cause for this to happen.

I have my thunderbolt cables and ports color-coded. So, I am definitely not switching the cables around.

More info:

This is how my mission control settings look like.

[NO] Automatically rearrange spaces based on most recent use?

[Yes] When switching to an application, switch to a Space with open windows for the application.

[No] Group windows by application.

[Yes] Displays have separate Spaces.

Does anyone else have the same issue? If so is there a fix?

Yes! I have 4 external monitors and this drove me nuts until I figured it out. Play around with moving the "top" bar between screens in the Arrangement window. Assign it to different screens and you will notice it will solve your issue once you find the "right" screen. I can't remember why that worked, but it did.

I'd take a screenshot for you, but I'm travelling and without my glorious monitors :)

Apple Support helped me out with this:

• Go to the Finder (click on desktop) and then hover over the "Go" menu at the top of your computer screen


• Now press the "option" button while still hovering over "Go" and you will see the "Library" folder choice appear


• Choose "Library" by highlighting it.


• With the Library folder open in front of you, locate the "Caches" folder.


• Now drag it to the trash.


• Empty the trash.


• Restart.

Eureka! This solved this annoying screen switch problem for me in mission control, where my Mac desktops would automatically switch by themselves when working in one of the four open Mac desktops.

For me it's based on which cable I plug in first, even when I plug them into the same ports. I'm using two HDMI cables. If they end up swapped, I just unplug one of them and plug it back in. If they're still swapped, I unplug the other one and plug it back in, the screens will both flicker and they'll swap back to normal.

This is an OS bug IMO. There's no reason the Macbook shouldn't be able to detect what's plugged into the port and keep the desktops on the same device they were on last time.