I have a Hoodman STEEL UDMA reader, and when Lightroom is running the SD or CF card gets ejected after about 1 minute. Once I shut down Lightroom, the ejecting stops.
Running Mac OSX El Capitan - latest Lightroom CC.
How good is the USB3 card that the reader is plugged in to?
I had to get a better USB3 card as the first one I got was crap (which I knew from the reviews when I bought it).
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