game has odd delay

At about 7 minutes into each game i get really bad delay on keyboard and mouse doesnt work properly but the game runs perfect set at 67 ms 70 fps solid the whole time but everything i do is delayed and my mouse wont even move in the direction im trying to go or ill hold tab for 3 second let go and itll still have the score board up for another 10 seconds with no key being hit ive uninstalled and ran the repair and nothing on some patches it doesnt happen on others it last a whole game instead of lke 5 minutes the mouse works just fine if i tab out and slightly when tabbing back in the second the game comes fulyup instead of a minor black screen it starts to do the lagging thing i dont know what to do and would like to hear any advice you have