Almost silent “pickup item” sound in Mac OS X v10.8

Since I've upgraded to Mac OS X v10.8 I barely hear the “pickup item” sound. I think this is a Java related issue but I'm not sure. It's not specific to Minecraft 1.4.x I can't hear the sound in Minecraft 1.3.x neither.

This sound is very important for the feedback, and also for the satisfaction of picking plenty of stuff floating on the ground