+1 on Slipin's suggestions. If you go through Lisa's lessons here, she would call those "micro adustments".

Something else that comes to mind it take a look at the angle at which your fingers are coming down on the fretboard. This may be part of what Slipin was getting at, but I'll elaborate.

You may need to bring them down at less of an angle - more straight up and down or perpendicular to the fretboard. 2 things that can impact this - 1) you are holding the guitar at an angle and twisting it so you can look down at the fretboard. This is common with those starting out because you are so focused on what your fretting hand is doing. Stand up with your guitar to discourage yourself from doing this. 2) On your fretting hand, push your arm forward to get more of an angle between your wrist and your arm. This will force your fingers to come down on the fret board more perpendicular.

If you haven't already, you might want to revisit Chris' lessons on posture. As simple and rediculous as it may seem, what he talks about there really matters and helps and he illustrates it very well.

Good luck!