In order for the MQA authentication process to work correctly the file’s metadata tags need to include codes that the MQA decoder verifies. If you have edited the metadata of your MQA files then the tags may have become corrupted. This is a very common problem as the tags and artwork provided with the files may not match a listener’s preferred metadata tagging convention. This is also a common issue with files ripped from an MQA-encoded CD.
This problem is easily solved using the MQA Tag Renaming Application. When run against files that are exhibiting this issue this application will read the MQA markers in the bit stream and apply the appropriate metadata tags to the files. More information on the Tag Renaming application can be found here: https://www.mqa.co.uk/customer/tag435sdf43te