Several posts to the WinDBG list recently have pointed out the fact that 1394 debugging can be flaky with the wrong hardware. If you’re having any sort of flaky experience with 1394 debugging, the first thing to do is to get a reasonable 1394 card. The kind folks at OSR have a 1394 card for sale in their store that everyone agrees works well with 1394. I can’t provide a direct link because their website seems to be smarter than I am at this hour – I am unable to find a direct link that works. They list it for US $29, which is a bargain at twice the price if you’re currently putting up with crummy 1394 debugging.