What component did Elon Musk initially hypothesize failed during the pre-test countdown?

Answer

A nitrogen COPV located within the payload bay

Preliminary telemetry suggested the primary hypothesis was the failure of a Composite Overwrapped Pressure Vessel (COPV) containing nitrogen, situated inside the vehicle's payload bay, which ruptured below its specified proof pressure.

What component did Elon Musk initially hypothesize failed during the pre-test countdown?
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