Pretty strange problem, I've never seen it before. If I were you I would go over to your startup page (launcher) and click "Edit Profile" on your main profile and follow these steps:
1.) Find the button that says "Launcher Visibility" and check the checkbox.
2.) Select the dropdown menu to the right of the checkbox, once open select "Keep the launcher open".
3.) Save profile.
4.) Once saved you should return to the home screen, from there you should see a top menu with 3 tabs: Update Notes, Development Console and Profile Editor. Click Development Console.
5.) Press play and do what you need to do to get it to not respond.
Find the button that says "Launcher Visibility" and check the checkbox.
Select the dropdown menu to the right of the checkbox, once open select "Keep the launcher open".
Save profile.
Once saved you should return to the home screen, from there you should see a top menu with 3 tabs: Update Notes, Development Console and Profile Editor. Click Development Console.
Press play and do what you need to do to get it to not respond.
After you have completed all of those copy and paste the text in the development console and send it over to Minecraft Support (https://help.mojang.com/) and post a thread with the text from the development console. They should be able to get into depth on how to fix it! Good luck!
