As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DISCREPANCY: #1 ENGINE COMPRESSOR STALL IN CRUISE, TEMP -53C WITH NEGATIVE CLOUDS. ALSO COMPRESSOR STALL WITH THRUST LEVER INCREASE FROM CRUISE SETTING OF 92.5 N1. CORRECTIVE ACTION: BORESCOPE OF COMPRESSOR FOUND MINOR BLADE CURL ON LPC 2ND STAGE BLADES. DATA SENT TO DELTA TECH OPS FOR EVALUATION, APPROVED FOR CONTINUED OPERATION AS IS.