Running 10.1.1 of Parallels, with a Windows 8.1 guest, pretty standard/recommended settings for development work. Computer is a MBP, Retina, 15-inch, Early 2013. Core i7 2.7GHz processor, 16 gigs of RAM. PCI-E storage. Sometimes when I am working in the guest (in a window), it will stop registering my input. The machine isn't frozen (things are still animating on the screen) but clicking/typing doesn't seem to register. If I focus on another OSX window, and then come back to my virtual machine, everything seems better. Has anyone ever experienced this issue? Pretty strange. Thanks!