Hibernation resets state of all drivers, please test with standby(S3) as it is not going to reset drivers completely.
S3 does not help. We use S3 as normal operation for standby constantly.
Then I would assume it is some OS / driver level issue as driver reset (with S4) seems to help to solve the issue.
But it's definitely related to the way MP uses the hardware (I mean uses DirectX), because I cannot reproduce that with other DirectX benchmark / games.