Camera Issues?

[thisisred]

Okay so I've got a simple video record up and running with FMS. Basically you record a video and review it at right. Later you'll submit it to the rest of the site etc, but right now I'm JUST testing the record. It works fine on my MacBook Pro with built in iSight. However I've asked a few people to test it and they can see themselves, but they cannot record video. It does, however, record their audio...

Any ideas why this might be happening?