Hi Darren,
I checked out your source and I think I may have found the cause of your problem, I cut and pasted a couple bits of code from your page below:
value="../56k/power stretch.wmv"
src="../56k/power stretch.wmv"
Notice how there is a space between "power and stretch" that may be the cause of your problem seeing that some browsers do not recognize the space in a filename.
Try closing the gap and see what happens
