TECHNICAL SERVICE BULLETIN - SERVICE ACTION: EXTERNAL AMP REPLACEMENT FOR NOISE/NO SOUND ISSUES (SA520): This bulletin has been revised to include additional information. New/revised sections of this bulletin are indicated by a black bar in the margin area. This Service Action (SA520), along with SA521, supersedes SA494A, which is now closed. Please follow the updated information in this bulletin. This bulletin provides the procedure to inspect the audio sound system in different modes and, if necessary, replace the AMP on some 2022MY EV6 (CV) vehicles produced from November 17, 2021 through January 7, 2022. Depending on the inspection results, the external AMP may or may not need to be replaced.