MP3 tag info - Comment field, and album art

 

I've got a nuvi 750 and I have a couple questions about the media player. It generally works pretty well and I think it's got a good design. However I have a couple issues that I don't see with any other mp3 player I use, whether it's on a computer or device (like iPod).

My first question is what tag versions it can handle, and if multiple tags are present which does it process? I use ID3V1, ID3V2 and APE tags in all of my MP3 files, and I notice that the Comment field is chopped off after the first 22 or so chars, which kinda makes it look like it only process ID3V1 tags (or will look to process them first if they exist). I actually use the Comment field and would like it to display a few more chars.

My second question is in regards to album art, and this is probably a more technical question. I embed album art in all of my mp3 files, and it displays fine in iTunes, WinAmp, my iPod, Windows Media Player, etc. but sometimes it does not display on the nuvi. I've found that if I use MP3Tag (and ONLY that program), I can copy the image from the tag, delete it, paste it again, save the file and it will display properly on the nuvi. So that kinda looks to me that the nuvi 'likes' the format that MP3tag saves the extended data in. My question is why the nuvi has a problem with the album art display but nothing else I use does.

If anyone has a link to a technical reference for how the nuvi processes mp3 tags I'd appreciate seeing it. I've searched but can't find very much.