Black Screen AFTER a game, long standing issue

After playing a game (all game types) the screen goes black and my whole computer is frozen until it eventually stops 5 to 15 minutes later. Some times a screen will pop up saying there was a connection error and then exit out of the client.

Method: Play any game type to the end (win/lose/surrender is irrelevant) Hit "Continue" Screen Goes Black Wait 5 to 15 min Afterwards the following options happen 5a. Go to end of Game lobby as normal 5b. Go to end of game lobby but hit Skip waiting for Stats 5c. Error message pops up saying connection Error (after hitting Okay, client is exited)

This has been a long standing issue and has persisted through patches. It did not used to always happen with my comp and I do not recall when it started. Whenever I am using voice chat, the communication is gone until the screen is no longer black EXCEPT for when I use Curse and then I can only hear but not respond. I have played games with the chat services closed and the problem is still present.