I actually try not to crank up the metronome too much when I'm playing, the louder it is the more distracted I become by it while I'm playing. Instead, I turn it to the point where I can pretty much hear it at a mf dynamic, that way I know its still there, but I'm not so entirely focused on it that I forget what I'm actually doing with the music.
You may also want to try some rhythm exercises. I recommend Robert Starer's book (I think its called Rhythmic Training) to help with more complex rhythms.
Try counting with the metronome, count quarters for a while, then change to eighths, then triplets, then sixteenths, etc....and go back. Also try counting each beat as a number starting going up to 8, then decrease by a number each time. (For example: 1,2,3,4,5,6,7,8,1,2,3,4,5,6,7,1,2,3,4,5,6etc...) These exercises really helped to improve my ability to sight-read and correctly count rhythms.