While messing around with Cocos and the CocosDenshion sound engine I ran into an interesting problem. I got the CocosDenshion drum pad example to compile by adding the required frameworks but on runtime only one button played a sound in the simulator. After going through the source code I figured out that the difference between this working button and the others was that the working button triggered background music and the others used the sound engine.
I then tried to use the SimpleAudioEngine and got the same results - great sound while playing background music but no audio when using playEffect.
After some experimenting I tried the drum pad example on another computer and there it worked perfectly! Any ideas on why my old MacBook Pro only plays background music but no effects?