This is really late in answering your question, but for the benefit of anyone else having this problem. I’ve had similar problems capturing via firewire from the Sony deck (M35U) that corresponds to this camera and this works; for some quirky reason, the order of connecting the camera/ deck is important.
Don’t turn Mac computer on yet. Check the deck settings.
1. Connect firewire to computer ( BUT NOT DECK).
2.Before connecting the iLink cable, set HDV/DV SEL and i.Link Set in the in/ out record menu. (Otherwise, the edit machine may not recognize the unit or may freeze).
3.Plug firewire into the deck. Turn deck ON.
Power up Mac.
Launch Media Composer.
MacPro 10.6.2
2 x 2.26 GHz QuadCore Intel Xeon
Avid Media Composer 5.0.3