It doesn't seem likely AA files could be converted to AAX format, because AA is of lower quality and you can't make it any better with simple conversion, but perhaps there is some specific use for such aa to aax conversion. In any case, if you want better audio quality, you have to look for the original AAX.
This conversion entry was verified by us and conversion was flagged as wrong or not possible.
Usually this happens when the conversion would try to convert different types of data between each other, such as audio to image, or it is not possible because incompatibility between programs, caused by closed file formats, very limited support etc.
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