What was found
AT FL 350 WE RECEIVED A CABIN ALTITUDE WARNING MESSAGE. AFTER DONNING MASKS WE RAN THE QRC AND THEN RAN QRH 2.1.1. WHILE RUNNING THE CABIN ALTITUDE EMERGENCY CHECKLIST WE CONFIRMED THE CABIN ALTITUDE WAS 11000 AND CLIMBING. FROM THERE WE COMMENCED AN EMERGENCY DESCENT. DURNING THE DESCENT WE GOT AN CABIN AUTO INOP AMBER MESSAGE. COMPLIED WITH THE CHECKLIST. REPLACED DUCT HOSE (AS1505-28A0032 IPC 21-51-15-01 ITEM 217) AND CLAMP (STBC10GG234 IPC 21-51-15-01 ITEM 215) PER ABOVE REF. RAN BOTH AIRCRAFT PACKS FOR LEAK AND OPS. CHECKS NO LEAKS NOTED, OPS. CHECKS NORMAL. BITE CHECK OF CABIN PRESSURE CONTROLLERS SHOWS NO FAULTS OR FAILS. PRESSURIZED ARCRAFT PER ABOVE REF. NO LEAKS NOTED, LEAK DOWN RATE WITHIN LIMITS PER FIG. 203 OF ABOVE REF. ACFT OK FOR SERVICE.