As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING DESCENT WHEN SPEED BRAKE/ SPOILER HANDLE WAS MOVED AFT RT HYD SYS PRESS DROPPED TO 0 AND QTY EVENTUALLY INCREASED FROM 13 TO 18. LATER WHEN SLAT HANDLE MOVED TO EXTEND LEFT HYD PRESS DROPPED TO 0 AND LEFT QTY INSP AND REPLACED SYS PRESS RETURN CASE DRAIN FILTERS BOTH SIDE NO METAL FOUND. NDS LEAK CHECKED SERVICED BOTH HYD SYS AND BLED SYS. LEAK CHECKS OK, RAN ALL HYD SYSTEMS, PRESS INDICATIONS NORMAL.