I have been using a Panasonic AJ-PCD20 P2 card reader for a few years on a Mac Book Pro. I used to use the FW800 connection to download to the computer and then transfer to an external drive. I changed over to using the USB connection to download the footage to the Fire Wire connected external drives to skip a step. This has worked fine. Now I am selling the equipment and tested the FW800 connection on the card reader and it does not mount on my Mac. Any thoughts? Thanks.