I'm not 100% sure on why this happens. It's been happening since about two or three months after I built my computer. Essentially, as the title states, whenever Blockland gains focus after using another app, the game hangs for 5-10 seconds, during which time, pressing more than about 3 or 4 keys will crash the game.
After blockland's done hanging, the message
"Window reactivating.." is displayed, between four and 16 times.

This happens on both steam and non-steam version with no add-ons enabled.
This issue definitely has been hindering gameplay. I didn't mind much before since I didn't alt tab often, however now that I'm working on a mod it's definitely getting in the way.
DXDiag + System Properties (Click for full size):



console.log (Starting Blockland, unfocussing the window, and refocussing it) -
http://puu.sh/aPcIg/b6365110aa.logAny help with this issue is greatly appreciated.