VirtualBox 5, Drag/Drop issue

[2fast4u]

I'm using VirtualBox 5
Host OS: Windows 8.1 Pro x64
Guest OS: Windows 7 Pro x64

Drag and drop works first few times, afterwards the guest freezes.

Task Manager on guest reveals vboxtray.exe using 100% CPU.

Only way to recover is to force close the VM.
This happened multiple times.

[noteirak]

Please read Minimum information needed for assistance and provide zipped attachment of the VM log file and the guest settings.