As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING CLIMB A LOUD HISSING NOISE WAS COMING FROM THE FO'S WINDOW. PRESSURIZATION WAS NORMAL. AS WE CONTINUED TO CLIMB THE HISSING NOISE LESSENED AND THEN WENT AWAY ALL TOGETHER. GROUNDED - YES. FOUND LWR FWD TRACK ROLLER DETACHED FROM SLIDER WINDOW FRAME. REINSTALLED W/SHIMS REF AMM 56-12-11 2. (6)(9)(C) AND (D). REINSTALLED WINDOW REF AMM 56-12-11-400-801 ACC WINDOW HEAT SYS TEST REF AMM 30-41-00-710-801.