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U3224KB, two MacBooks, MacBook A TB not disconnecting
Hello,
I have two MacBooks (let's call them A and B). MacBook A is connected via Thunderbolt 140W, and MacBook B is connected via HDMI.
When MacBook A is active, everything works fine, and the Dell monitor acts as an extended display for it. However, when I switch the Dell monitor's input to display content from MacBook B, MacBook B correctly starts using the Dell monitor as its extended display, but MacBook A doesn't seem to recognize that the Dell monitor is no longer connected to it. The system preferences still show two displays, and the mouse can move off-screen into the space where the Dell monitor used to be, as if it were still connected. Also, any windows or applications that were on the Dell monitor do not return to MacBook A's main screen but remain off-screen.
Has anyone experienced a similar issue or knows how to make MacBook A automatically recognize when the external monitor is no longer displaying its content? Any advice on how to fix this would be greatly appreciated.
Thank you!
Chino de Oro
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April 4th, 2024 01:22
It's working as designed. When you switched device and assigned the monitor as an active display for Mac B, the monitor signal was disconnected from Mac A. Therefore, it's normal if monitor was not recognized as being connected to Mac A.
guid
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April 4th, 2024 18:39
I wish you had read my post thoroughly. In my post, I clearly mention the problem is that when I switched device and assigned the monitor as an active display for Mac B, the monitor was not recognized as being DISconnected to Mac A.
You even didn't read the title.
(edited)
Chino de Oro
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April 4th, 2024 19:37
My bad, I was focusing on this statement as the main issue "but MacBook A doesn't seem to recognize that the Dell monitor is no longer connected to it."
guid
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April 5th, 2024 00:25
Chino de Oro
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April 5th, 2024 01:48
You can also edit the original post to update the monitor info.
Just some thoughts regard troubleshooting, test the same setup but with Mac A connected to AC adapter to rule out if power delivery has kept the connection alive. Or, test with Mac A connects to a different connection such as mini-Displayport (if applicable).
DELL-Chris M
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April 5th, 2024 10:48
To receive assistance from Dell support agents they need to first verify the ownership and warranty status. Click the blue "Get Help Now" on the right to start a private live chat session. Share the private Service Tag with them.
* Open the U3224KB Menu
* Go to Input Source
- Set Auto Select to Off
- Set Auto Select for Thunderbolt to No
* Exit the Menu saving changes and retest switching from MacBook A to MacBook B