as it stands when you add audio to an nft it shows up in its own separate player, but on sites like opensea the audio player actually shows up UNDER the main image so that you can enjoy it while viewing the image, without making it a movie file
this is important because an mp4 set as the main image if it is too big will simply not show up - thus if there was say a playbutton watermark over the image in the preview mode on the market - and then you click it and it goes into the nft with the preview image (playing if animated) with the audio under it that autoplays this would be ideal.