you are not being clear here about your firewire drive. From the old 2 Gig computers, to the current MAC Pros, and everything in between, you need AT LEAST a FW800 card to do DVCProHD. If you are using a FW400 drive, I have no idea of how you got it to work reliably all these years, but you should have been playing the lottery. You can’t do DVCProHD on a FW400 drive. As for SATA drives, which is all I have been using in countless systems for the past 1 1/2 years, you need at least TWO SATA drives stripped RAID 0 to get reliable playback of DVCProHD. If you are in a MAC Pro, stick TWO SATA drives into the MAC Pro, stripe them together with Apple Disk Utility RAID 0, and you will have no problems. You can use AJA Kona System test to test the speed of the drives. Two SATA drives will give you about 120mb/sec, which is more than enough to do anything with DVCProHD.
Like I said, you were not clear about your FW drive – FW400 or 800. If your 800 is giving you drop frame errors, there may be issues with your drive, but if you can’t get your FW400 drive to do DVCPro HD, well, no one can. And if you have been doing it for the past two years, well, you are lucky.
Also, I assume that you have gone to EASY SETUPS in FCP, and selected the AJA Kona DVCProHD codec.
Bob Zelin