The Secretary may revoke or suspend any license issued under the provisions of this subtitle upon satisfactory proof that the license holder has violated any provisions of this subtitle or any rules and regulations adopted under it. However, no license may be revoked or suspended until the holder is given a hearing by the Secretary after reasonable notice. If the license holder fails to appear at the hearing after notice and contrary to rules and regulations, the license may be suspended or revoked. This section does not limit the right of the Secretary to proceed as authorized by other sections of this title.