iTunes visualizer is choppy until I start other apps
I just noticed a strange behavior of the iTunes 11 visualizer on my MacBook Pro: it looked slow and choppy. No other program was running. Since I assumed memory problems to be the cause I started Memory Clean. Starting it (not even executing it) immediately made the visualizer run smoothly. Even stranger, upon quitting Memory Clean the visualizer was choppy again. I tested a couple of other apps whether they had similar effects on the visualizer: Firefox did not, Word did not, but iPhoto did. Again, starting iPhoto made it run smoother, quitting iPhoto reverted it back to choppy. I have a feeling that not only the visualizer might be affected because I have the overall impression that my Mac used to be more responsive. But I might be wrong about this.
Any clues are much appreciated!
Max
MacBook Pro, i7, 2.8 GHz
OS X 10.8.4
iTunes 11.0.4
MacBook Pro, Mac OS X (10.7.1)