The term "Pro 406" is not a standard product name from the developer, Audiophile Inventory. However, based on available data, there are two possibilities for what you encountered:
The software's core philosophy is to provide meticulous, computer-based processing that removes the computational burden from playback devices. By converting complex audio files offline, AuI ConverteR PREP 406 allows your Digital-to-Analog Converter (DAC) to focus solely on playback, free from the constraints of real-time processing. This results in cleaner sound, improved accuracy, and less battery drain on mobile devices. aui converter 48x44 pro 406
AuI ConverteR 48x44 PRO 406: The Definitive Guide to High-Resolution Audio Conversion The term "Pro 406" is not a standard