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Phone lights flashing, won't boot

I am running into a strange issue where a phone won't boot.  It is a 7940 running 8.4.2 firmware.

When plugged into some ports, the phone works fine.  It attempts to go through and upgrade, but fails and uses its current.

When plugged into some other ports, all light flash at the same time consistently, and the phone screen remains blank and does not boot.

Port configs are the same.  The problem is so random that it is hard to tell if the problem is the switch, or communication to CUCM with the phone.

has anyone ever experienced this?