Admittedly, this is a bit esoteric, but it’s something you might want to keep in mind. I have an iSight and have found a potential conflict between it and my external firewire drives (including my iPod). This originally manifested itself as a clicking sound coming from my iPod. Transfers to it were REALLY slow, and I thought maybe the hard drive was failing. After a lot of debugging, it turns out that the problem wasn’t with the iPod. Having the iSight plugged in made the iPod slow down randomly… Soon as I unplugged the iSight, the iPod started updating at it’s normal speed. This is also probably why the iPod showed no odd behavior when I took it into the Apple store to have it checked out.
The worst part of this story is that it also corrupted the directory info on my external firewire drive (a Lacie 120 GB). It got further messed up when I tried to run DiskWarrior on it with the iSight still plugged in (this was before I figured out what the problem was). I may have lost a bunch of video data at this point. 
Other people have been reporting this problem on the net, so I’m feelng more and more confident that this isn’t a hardware failure on my end, but a bug in software or hardware. I’m disappointed in Apple about this… one of the reasons I bought into Macs (aside from OS X) was that stuff “just works” on the Apple side. The iSight so far is causing more problems than not.
May 31st, 2004 at 1:10 pm
Dude, thank you so much…I have spent the past hour and a half trying to troubleshoot the slooooooowness of my iPod on my mom’s comp, unplugging the iSight immediately did the trick.
You’d think Apple could get their own software/hardware to work with itself, wouldn’t you? :\
Thanks again.
May 31st, 2004 at 2:37 pm
What bites, though, is that it means this is still a problem… if you’re still around, what version of OS X are you running?
September 18th, 2004 at 12:37 pm
This problem continues. I am running OSX 10.3 + all updates that Apple has offered. I am running a 2nd generation 30GIG IPOD. Apple has yet to address it in any meaningful way. I just unplug my iSIght when not in use. I am annoyed as well since all of this is Apple hardware.
October 21st, 2004 at 12:50 pm
I too have had the problem. I don’t know what the deal is. Here’s something even stranger. The problem doesn’t happen “as much” for me if I use the firewire cables that came with the iSight, but if I use the SightFlex (by MacMice - http://www.macmice.com) it happens all the time. WTF is that about?
June 6th, 2005 at 4:27 pm
I have a similar problem with a dual 1.8 GHz G5, iSight with 1.0.3 update, and a iPod Photo 60G
Any workarounds aside from disconnecting the cable?
June 30th, 2005 at 7:37 pm
Same problem here on a 20″ iMac G5. This stinks as it appears it has been going on for many over year with no fix.
July 26th, 2005 at 4:21 am
i have my thumb on this issue, dear friends, since the year 2000 and system 9.2, when i had the same problem with connecting Sony dv camera. i was *never* able to dump video from the camera to the external hd. how handy :6
perhaps it’s a problem deeply rooted in the fw400 protocol, since not even years of hardware revisions seem to prevent it. apparently a nasty skeleton in apples’ wardrobe, considering how meticulously they go about expunging related posts on their support forums… oh well, we’re in the mids of 2005, just for the record.
October 14th, 2005 at 4:36 pm
I have a similar problem. Doing a unicast with Quicktime Broadcaster to another computer on a LAN, when after about two minutes, the video data rate slows to zero and the video freezes. Audio stays connected just fine. Only Video. Apple tech was of no help. Broadcast from one iBook to another using 10.3.9 is great when it stays working.