Hello SteveRansbottom-7509,
Thank you for posting in our Q&A forum.
Please check or troubleshoot the issue on one PC with the issue.
1.Based on the description "Remoting to these devices, I can see that an application I am in, loses focus, then it will return. ", would you please confirm whether the issue occurs in such specific application or the issue can occur in any application?
2.If the issue can occur in any application, would you please check whether the issue can occur when you are in the Safe Mode.
Start your PC in safe mode in Windows
https://support.microsoft.com/en-us/windows/start-your-pc-in-safe-mode-in-windows-92c27cff-db89-8644-1ce4-b3e5e56fe234
3.If the issue occurs when you are in the Safe Mode, it may be the system driver\device driver.
Please verify all the driver on the problematic PC based on the following link and check the result.
4.If the issue does not occur when you are in the Safe Mode, it may be the machine hardware problem.
Hope the information above is helpful. If you have any question, please feel free to let us know.
Best Regards,
Daisy Zhou
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