I've been playing with a metronome for years and realized the mind game I was playing with myself and figured I'd share it with you and a method to overcome it. Try this exercise: Set your metronome to 160bpm. Start playing quarter notes concentrating on time, tone and consistency. At the same time pay attention to your breathing and any tension that you have in your body. Now try this. Set the metronome to 80bpm and do the same thing playing eighth notes. Seems a lot easier doesn't it. Now try this. Set the metronome to 40bpm and do the same thing using 16th notes. Seems even easier doesn't it. Interestingly at all 3 tempos you are still playing at the same speed. I believe it is because when you hear the click going at 160bpm it makes you a little nervous and you stop believing that you can play at that tempo.and you tense up. Yet when the click is going at a lower tempo your mind doesn't play the same trick on you and you don't tense up even though you are playing just as fast. Now that you have done this exercise and noticed it try the quarter note at 160bpm again and realize that you can already do it perfectly as you have already done it at that same tempo just relax and do it. C/S, Rev J
A bass teacher showed me this exercise, and it helped me a lot. When the BPM is really fast, it becomes obvious when you are a little off. When its really slow, you rely a lot on your internal clock; you're forced to hear the music in your head. Both ways are good practice exercises.
For me, throwing the metronome out of a third story window would solve the problem, but that's just my opinion.