Wallhacks are definately the hardest to catch, you also have to be aware of what the player can hear. there hasnt been a single session where someone hasnt accused me of wallhacks, but there also isnt a single session where im not using headphones.  If anyones ever running near me ill know where they are. u can usually catch wallhackers cause they either preaim, or dont check common spots when no one is there but happen to check them when they are. also if anyones ever hacking, 99% of the time they also have wallhack.