Washed out color in QuickTime videos on Windows machine

I recently shot a video for my church using an older Sony camera in HDV format. I edited the video in FCPX, and the colors looked fine in the FCPX timeline -- bright and rich. I exported the file using Compressor in H.264, 1920x1080 for projection in the church, and in .mp4, 640x360 for website display. The colors looked fine in the church projection (the QuickTime file was run on a MacBook), and they look fine when the website version is displayed in a browser running on a MacBook. However, when I view the video in a browser running on a Windows machine, or simply display the video in QuickTime on a Windows machine, the colors look totally drab and washed out, like a nasty grey filter was applied. I know it is not my Windows computer display, since other web videos look just fine. If you want to see what I am talking about, check out http://www.newsongchurch.com/ministries/small-groups/index.html.

I spent hours one day researching this issue in old discussion groups posts. I tried a lot of different suggestions that I found:

--Encoding using x264encoder and changing the settings for the "nclc atom" and "gamma 2.2"

--Use JES Deinterlacer to change the same variables

--Increase gamma settings in Compressor

I must have exported the video 25 times with different settings and nothing seems to work. It is incredibly frustrating to work for days shooting and editing a video and then have it look like poop on Windows machines (which is what most people will use to view this video). In the 6 or so years I have been using Final Cut, I've found that it takes way longer to find the right export settings than it does to edit!

Does anyone have any thoughts about how I can make this video look the same on both Macs and PCs? Please let me know if you need more information about my project. Many thanks in advance!