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TPS63011: What happens if FB is not connected? Seeing odd behavior.

Part Number: TPS63011

A handful of PCBAs in a recent batch are exhibiting problems with the 3.3 V output from a TPS63011-based circuit.  I've attached a screenshot of the schematic.  We're suspecting a bare-board fab or soldering problem, but we're trying to get a better understanding.  Input voltage is 4 VDC from a bench supply.  The EN pin is high.  Here are the symptoms:

1.  Under no load, the output is 3.5 to 4 V.

2. Switching node looks bad -- noisy and jittery.

3.  Under even a light load the output drops.  For instance, with 100 ohms load the output is 2.5 V with noticeable ripple.

If the FB pin were to be disconnected or poorly connected, could that explain this?

Is it possible for the IC to damage itself upon first power-up if FB is floating, and thereafter exhibit the above problems?