LTC6268 behavior during recovery

I am attempting to reset the capacitor of an integrator circuit by shutting down the chip (driving pin 8 with a 4 usec low-active pulse) and pulling the output down with a 10K resistor (capacitor is 3.3 pF). Discharge of the capacitor should occur through the input protection diodes. Circuit behavior indicates that the integration function does not occur as the output moves from low to high at 620 nsec following the trailing edge of the shutdown pulse. The negative input is observed to come to -320 mV and stay there, regardless of the drive voltage.

In essence, is there a delay time after release of shutdown until amplifier operation resumes? What is the behavior at the inputs during shutdown until recovery is complete?