I am starting a new thread here to post my solution, since so many other threads were opened on this topic. I am cross posting on a number of sites, too, since so many people are having a similar problem. Apologies for that, but I am trying to spread this solution. Took me about six months to figure it out on my own. Basically, the problem is that under Windows 7 (I am running 64 bit, but it may also occur under 32), users experience a CPU spike accompanied by an annoying "buzz" from the speakers every ten seconds or so. This is most noticeable when playing media files, as the buzz isn't heard when there is no audio running. Some solutions that folks have suggested have to do with muting the mic, removing EMF sources, updating drivers, re-installing Windows (of course) and reducing the bit rate on the audio output. None of them work. I found the problem to be associated with iaantmon.exe -- the executable for Intel Matrix Storage Event Monitor. About every ten seconds or so, it would spike, causing the problem. Iaantmon.exe is almost exclusively (but not totally) for RAID setups, which is not (absolutely) necessary when running a simple laptop with a hard drive system. I threw in lots of caveats there because it is reported to help performance in other areas, such as battery life, but I cannot confirm this. Maybe others can chime on on those points. To fix, create a restore point, run MSCONFIG and disable iaantmon.exe from startup. Reboot, and enjoy some peace and quiet, along with your music playing smoothly once again. Again, whether or not you need this process may have to do with your personal setup, and whether you are using RAID, etc. But you CAN disable it and reboot without any problems, at least when using a normal hard drive setup. Please be careful with other configurations, but this shouldn't brick your PC if you do it, at least. If anything changes, or if I find out more, or if I notice some long-term performance degradation from disabling the process, I will update here. But it seems this is the solution.