when I export a file as MP3 with 320 kbps quality via Audition, frequencies between 16 kHz and 20 kHz are cut off. this problem is independent of the source file. for example, when I export a FLAC file as MP3 this happens. When I edit a full frequencies range MP3 file (20 Hz - 20 kHz) and than export it this problem also happens too.
The funny thing is that when I do the export process with Audacity which is a free and open source software, this problem does not happen. I tried the same experiment with other paid softwares such as Acoustica 7, iZotope Ozone 9, iZotope RX 9 Audio Editor, and as I mentioned, frequencies above 16 kHz are not cut like Audition in any of them. I think this problem is caused by Fraunhofer MP3 Encoder but I can't do anything to change it.
So I ask you developers to solve this problem. Instead of Fraunhofer MP3 Encoder, you can use LAME Encoder like other softwares as I mentioned above, or at least you can add a setting to the program where we can change the Encoder even if you do not use it officially, thanks.