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On two occasions we have seen the EVR go into a bad state , (click on the "EVR" button in upper right of the andor ioc window) cause some camera to not trigger at all and one camera to glitch between a "locked" and "unlocked" state.  The fiducial-rate turns red and fluctuates away from 360Hz:

We recovered tried recovering from this once by rebooting the IOC (a previous time we power cycled, but that may be too heavy-handed)and it worked for some minutes, but in the end in both cases we had to power cycle the node.

USB Extender

http://www.icron.com/products/icron-brand/usb-extenders/fiber/usb-2-0-ranger-2324/

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