I am running a first generation iMac Intel Core Duo running on Mac OS X 10.4.10 I plugged in some Shure E2C earphones a few days ago to listen to iTunes and then took them out. After that however, I noticed that the volume of the iMac has decreased substantially. i.e: 4 bars of volume in the past was perfectly audible for me but now with 4 bars, I can barely hear anything. I was wondering if some setting got adjusted and if so, how I can rectify this problem. Any help would be much appreciated.