MyLink and SD Mystery

diannabill · April 16, 2014

I formatted a 32GB SD card (FAT32) and loaded quite a few albums on it. Everything worked fine--it didn't take an unusually long time to read and play.

Everything worked fine for weeks. Well, I couldn't have that!

I decided to remove some of the albums and replace them with others. But then every time I tried to play my SD music (all mp3 by the way), it would continue to show old removed Artists and Albums (even though the folders had no content in them). It would still read the new stuff and play them too.

I took the SD card in and out before pressing "Media", after pressing "Media", and I even tried some goofy door opening and closing ritual. (Apparently opening and closing the door is supposed to reset your mylink somehow, but since I open and close the door every time I get in and out I can't imagine how.) I pushed it in quickly, and even tried sneaking it in and pretending I wasn't interested. NOTHING WORKED--it still listed deleted artists and albums with no content.

I called my dealer who put me on hold forever while they asked around and then told me they had no idea. I tried calling the mylink folks who were nice enough to read the manual to me.

Finally out of desperation, I decided to reformat the SD card. I knew that would erase the card but I didn't care at this point. I did a "quick" format, which was really quick, then I clicked and dragged my music back on it.

Guess what happened when I put my card in? IT WORKED! Only the newly reloaded music was on there.

So my questions are: Is there something about deleting things on an SD card that somehow leaves some traces of files that still show up in MyLink (but not on my computer)? I only have the one SD card, so I haven't been able to figure out if it's just this particular card. Or is there something else I should be doing besides a simple delete? Or am I going to have to do the reformat and reinstall everything when I make some major changes to the card contents?

Any suggestions?

IndyAJW · April 16, 2014

Can't speak from experience, as i don't have my truck yet, but there's probably a hidden file on the SD card that contains a list/library of your media. Call it a catalog maybe. Was probably created when you first put the SD card into the truck and filled with the newest media...probably just not smart enough to update itself when removing media. I would recommend next time to look for the hidden file and delete that rather than format.

Others will probably chime in to provide better info....good luck

benw · April 16, 2014

When a file is 'deleted' it isn't necessarily removed from the SD card, the space it occupies is simply marked as available so that it may be overwritten later with newer files. This preserves the life of SD cards a bit by reducing the repeated writes (writing empty space counts as a write action) to the card. This is also why you can sometimes recover a deleted file from a drive. A Format writes over the space, fully deleting the files, not just the pointer to the data. Chances are, the operating system used in the trucks is caching the data in a way that it still recognizes files that are simply deleted. This is likely refreshed when the data can't be found, due to the format.

diannabill · April 16, 2014

When a file is 'deleted' it isn't necessarily removed from the SD card, the space it occupies is simply marked as available so that it may be overwritten later with newer files. This preserves the life of SD cards a bit by reducing the repeated writes (writing empty space counts as a write action) to the card. This is also why you can sometimes recover a deleted file from a drive. A Format writes over the space, fully deleting the files, not just the pointer to the data. Chances are, the operating system used in the trucks is caching the data in a way that it still recognizes files that are simply deleted. This is likely refreshed when the data can't be found, due to the format.

So are SD cards more "fragile" than other media, and have a more limited life of deleting and writing?

benw · April 16, 2014

So are SD cards more "fragile" than other media, and have a more limited life of deleting and writing?

Solid state memory in general. Although they've made a lot of improvements, it's still an issue, especially with cheaper memory sticks/cards. For purposes here, it would probably take a long time considering how often music would actually be swapped out with that much space.

TJay74 · April 16, 2014

Actually when you "delete" a file the program only removes the first block of data that has the info about the file. The rest of the file is still there until it is written over again or formatted.

russ9443 · April 16, 2014

If you removed the files from the SD card on a Mac, empty the trash before ejecting the card.

Sent from my iPhone using Tapatalk

diannabill · April 16, 2014

If you removed the files from the SD card on a Mac, empty the trash before ejecting the card.

Sent from my iPhone using Tapatalk

No, I deleted them on a Windows machine, but I think I'm going to try to "view hidden files" as IndyAJW suggested above and see if that avoids the problem. I don't intend to delete anything for awhile though.