Problem with FireWire import into Final Cut Pro from Sony DCR-TRV120
I have a ca. 2000 Sony DCR-TRV120 camera that has recorded digital video to tape (Hi8/DV cartridges). It has an i.LINK port, which is what Sony calls FireWire. I am unable to import video from the camera through Final Cut Pro, iMovie or QuickTime Player. The camera does not show up as an import source in any of those.
My computer is an M1 MacBook Pro running Monterey 12.3.1. The camera shows up in System Information:
So, there is some communication. It is hooked up through an Apple Thunderbolt 3 to Thunderbolt 2 adapter, which has an Apple Thunderbolt 2 to FireWire 800 adapter plugged into it, which, in turn, has a FireWire 800 to FireWire 400 adapter plugged into it. The cable that connects the camera has a six-conductor FireWire 400 connector on it and a four-conductor FireWire 400 connector on the other. The latter is plugged into the i.LINK port of the camera. The camera has the A/V→DV OUT option turned to ON.
Why can I not import video from the camera?
MacBook Pro 15″, macOS 11.0