My Dell n5110 does strange things ! ^^

Hi got my dell 1 year ago first it was the internal speakers they stop working both of them first was the right then the left but i have a  SteelSeries Syberia v2 so i was ok no problem i can do it without them but passed 2 months when im in a game like diablo 3 or league of legends my computer presses the ""Q"" Button byitself and its really anoying its like it starts auto pressing for 3-4 sometimes 10 seconds then it stopps ... the odd thing is that it does it only in some games .
In windows mode or skype or any other program i use it dosnt .
If someone has a solution ill be thankful.