Question regarding Win7 clipboard function and sandbox on CIS

I set anything that accesses the network, such as browsers and music players, to be sandboxed under CIS. I default the settings to limited.
I do have a problem that is common throughout all the applications running under the sandbox feature of CIS 5.10.228257.2253 and that is the clipboard function stops working after 10-30 minutes.
For example, Firefox will not receive any paste functions (or clipboard transfers) from the clipboard memory using any of the internal functions or even using CTRL-V.
If I run IE in the same manner, it also has the exact same problem.

I downloaded a few programs that allow me to monitor the clipboard memory and any PID’s that attach to it. When the paste function stops working in the sandboxed programs I checked for any programs attached to the clipboard and also verified the content of the clipboard memory. Everything seems to be fine.

I can copy text out of any program in the sandbox into clipboard memory but I can not copy that same text back into any program running in the sandbox.
If I open up some programs outside of the sandbox, copy and paste via clipboard memory works flawlessly between any program not running in CIS sandbox.

The only 2 messages I see in the defense plus logs are

accesses COM interface - of svchost.exe
DNS/RPC client access

after a period of time clipboard is unable to paste anything into any program running in the sandbox, it still works fine for anything outside the sandbox. I do not want to run these programs outside the sandbox but loosing the paste feature is enough to drive anyone mad.

Can anyone explain how I can exempt the clipboard function from being blocked or which feature I need enable/disable to try and diagnose what is causing this?

I have experienced this problem with manually sandboxed browsers in the past - it appears to be a sandbox bug. I wonder what sandbox level you are using?

If you are using partially limited, that’s the best you can do. The sandbox is rumoured to be being extensively re-written for CIS 6.0, so it may be solved at that point.

Best wishes