My rule of thumb is to never update the OS on systems I rely on for work, and that are working well. My FCP system drive is still on 10.6.8, for example. Updating the OS to the latest one, when two things you are using have been discontinued, isn’t wise. Mavericks didn’t take FCP7 into account when it was made…and AJA doesn’t update drivers for hardware it has discontinued for over two years now.
If you rely on FCP 7 and the IoHD…don’t upgrade. It might be wise to either partition your hard drive into two, and install older OS version onto that…or revert your whole system to an earlier version.
Why did you upgrade anyway? I only upgrade when I absolutely must, in order to make something work…and even then, as you can tell, I partition my drives, or install new OS versions on new drives. My MacPro has three boot partitions.
Shane
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