The device exhibited a metallic short between pin-5 and an internal circuit element (a resistor that would normally be isolated). The short appeared to be solder material (primarily tin) from the pin-5 termination that flowed into the device due to excessive temperature exposure during assembly.
Fig. A – Solid-State Relay
Fig. B – Decapsulated, bottom side
Fig. C – Metallic short between pin-5 and an internal circuit
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