As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DUCT SPLIT RT DUCT 44, LT DUCT BOUNCING BETWEEN 25 AND 30 PRESSURIZATION WAS NORMAL AFTER ALMOST 4 HRS IN FLT, RT DUCT 44, LT DUCT 35. ACFT GROUNDED. FOUND LEAK ON CONTROL PRESSURE SENSE LINE AND SUPPLY PRESSURE SENSE LINE. TIGHTENED B-NUTS DURING MM TASK 36-12-00, RAN ENGINES AT HIGH POWER. VERIFIED DUCT PRESSURE ON BOTH ENGINES WITHIN LIMITS. NEEDLES MARRIED.