As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
THE CREW REPORTED AFTER ENTERING ICING CONDITIONS AND ICE PROTECTION ACTIVATED, A LOUD THUD NOISE WAS HEARD FOLLOWED BY THE STRONG ODOR OF SMOKE IN THE COCKPIT AND WHITE CLOUD OF SMOKE BY THE LAST 5 ROWS IN BACK OF ACFT. MAINTENANCE INSPECTED AND REPLACED THE NR 11 MID COUPLING O-RINGS ON THE BLEED AIR SYSYTEM. PERFORMED OPS CHECKS OF BOTH PACKS. NO DEFECTS WERE NOTED.