Hello. I am looking to solve a problem with using my iPod and Audacity. I am using version 3.7.0 of 32 bit build Audacity and have installed FFmpeg so as to export M4A AAC audio files. The exporting generates M4A files and happens without error. I then use iTunes to import those files. The files play fine in iTunes. I then sync my iPod (7th gen. Nano). When I listen to those files on the iPod, they have “scratchy” audio artifacts in places. Those artifacts are not heard when iTunes plays the files.
How do I set up and use Export in Audacity to eliminate the “scratchy” audio artifacts that I hear in those files when playing in my iPod?
Is there maybe a custom FFmpeg format that I can use in Audacity to accomplish this? If so, what Format, and what Codec?
I would need explicit, easy to follow instructions on how to use Audacity to do any of this.
I found a thread on Reddit that said the encoder is using the PNS (“Perceptual Noise Shaping”) feature and that that is incompatible with iPods. It said to use “-aac_pns 0” in FFmpeg to encode a file without this feature. I don’t know how to do that; and I don’t see any way to enter a command line anywhere. Further, I see no executable FFmpeg file on my pc, and if I did, I wouldn’t know how to use it. Is there a way to have Audacity itself to turn off PNS when it encodes?
Thank you.