ok basically when you get into both, look for any tech notes pasted up like 'please do no touch high eq's' etc as there may be problems with the mixer what not. if everything is all clear, 95% of the time the dj before you is going to have the master up in the red's. bring it down, and dont ever turn it back up unless someone from the club or technical team orders you to for some reason. next with the eq's generally they are only used for cutting away freq's. But in the case that a track has had a bad mixdown/master you can use the mid's and high's to accentuate the higher frequencies and make them come out a bit more if the track is sounding to muddy through the soundsystem though. that wont happen to often though if like you say the knobs are all the way to the right, correct them to 12, and if the volume drops, have a look at rthe lights, and if the light is sitting way below the reds, push up the gain untill its hitting just above green. making sure the master dosent hit the red either.