When I watch your videos using my preferred browser, Chrome, the picture quality is poor - the edges of things look blurry or jagged. It's not a problem in Internet Explorer.
I used to have the same problem with YouTube videos, but after installing an extension called Disable YouTube HTML5 Player picture quality of YouTube videos on Chrome returned to normal. So, I'm guessing the problem is that your videos are designed to play using HTML5, and that Chrome doesn't play HTML5 videos very well.
Unfortunately, I can't find any way of generally stopping Chrome using HTML5 and forcing it to use flash, so for the moment I have to watch your videos using Internet Explorer.
I'm not expecting you to come up with any solution - I just thought you'd like to know about this, and other JPod101 users might find it useful to know too. Although if you do have any advice that would be welcome