As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
FLT 6701 - MADE AN UNSCHEDULED LANDING AT TPA. CABIN PRESSURE CONTROL DIFFICULT TO MAINTAIN. MAINTENANCE FOUND INSULATION MATERIAL HOLDING THE OUTFLOW VALVE OPEN. THE INSULATION WAS REMOVED AND THE CABIN PRESSURE CHECKED PER MM 21-30-00. (M)