To change the song MP3 comments within a pitch, first open the pitch edit modal.
You can open the pitch edit modal for an existing pitch by going to your Pitch Log and right-clicking a pitch. Then select Edit pitch to open the pitch edit modal.
Once the pitch edit modal is open, click the more options button next to a song and then select the Customize song option.
The customize song pitch view will appear. Type the comments into the MP3 comments field and make sure to save your changes.
Note: Changes made in a pitch only apply to that pitch.