As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
PACK 2 BLEED 2 KEPT FAILING DURING CLM OUT. THEN FA REPORTS POPING AND HISSING NOISE UNDER FLOOR RIGHT SIDE OF AIRCRAFT. A/I DFW ACCT NOISE FROM NR 2 ENGINE. EMERGENCY DECLARED. FOUND LINE BLOWN OFF NR 2 DUAL TEMP CONTROLLER. REINSTALLED LINE IAW ETNEM-21-056 OPS CHECKS GOOD IAW AMM 21-51-00. E2 BLD OPS CHECKS GOOD IAW AMM 36-11-05.