The banshee 2.41 rejected my mp3 sync with error: “The mp3 format is not supported by the device”
My device is an Iphone 3G
If you have not yet synced your iPhone with a computer running iTunes, you will need to do so first, before Banshee can properly sync to your iPhone.
if you can it, would be good if you could add the device in question to your question so we can help you better solve this (And also the version of Ubuntu you are using).
In some cases, the problem is that, since the MP3 format is a closed, proprietary format, then you need to first install the ubuntu restricted extras to have the ability to work/play with mp3 files.
Something along the lines of: