Through the summer I was using an FCA610 over USB very well with my Macbook, but lately it is constantly glitching, about once a minute. There is no glitching over Firewire as far as I have noticed but I need the flexibility of also using the USB connection on occasion.
I have checked the clock source in Audio/MIDI Setup (set to USB) and can't find any settings out of place anywhere else.
I would try updating the firmware but apparently I have to have a Windows machine to do that...
Thanks for any hints!
MR (Retina Macbook, OSX High Sierra)