As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
(CAN) AFTER 382.2 HRS IN ACFT, BLEED VALVE STARTED TO MAKE A HOOTING NOISE AND ALSO PRODUCED VIBRATIONS. ABOVE SYMPTOMS WERE ONLY SEEN ON PWR REDUCTIONS. THERE WAS A SERVICEABLE BLEED VALVE INSTALLED FROM ANOTHER ACFT AND PROBLEM WAS RESOLVED.