So I've been following the MBP forum for their Audio Volume issues because we seem to have the same problem. Check out their issues here: http://forums.macrumors.com/showthread.php?t=720941 There is also an apple discussion here. http://discussions.apple.com/thread.jspa?threadID=2037093&start=0&tstart=0 I have a Late 2008 MB running both Leopard and Boot Camp with Windows XP pro SP3. Under boot camp it uses the RealTek driver for the sound card. It is putting out very low volume. Many people have posted similar problems with Vista and windows 7. Here's the test I did to confirm. I made a 1kHz test tone audio file and played it out of OS X. I connected the output of my headphone jack to a volt meter and measured a little over 1V or 1000mV. I switched to Windows and played the same file. This time I measured 280mV. This proves that the RealTek driver is not sufficient and does not measure up the full potential of the Macbook. I've called apple on the issue and they say that it is not their problem and they do not support it. Even though they advertise that Windows is fully functional under boot camp. The solution for the MBP was that someone modified the INF driver file. Unfortunately, Apple uses a different chip in the MB and this solution will not work. I tried it. So PLEASE post here if you are having similar problems and/or if you have a solution to the problem. Thanks!