strange problem with USB flash drive (audio files getting mixed)

[Special K]

Every morning I load a set of podcasts onto a USB flash drive so I can play them in my car. Occasionally I will have a very strange problem where the mp3 files somehow get mixed. That is, I will be in the middle of one podcast, then I will all of a sudden hear some static, and then I will be at some random point in a different podcast on the drive. After a few seconds to a couple minutes, I will again hear static and will then be back to the original podcast.

Today I had an even stranger occurrence: I was listening to one podcast, but then it cut into a different podcast that had been deleted from the device the night before. After about a minute of this, it cut back into the original podcast. It's like the data from the original podcast wasn't actually deleted and there was somehow still a pointer to it on the USB drive.

Does anyone know what could be going on here? The obvious answer is "the flash drive is dying, get a new one", but I just ran several passes of Check Flash (http://www.softpedia.com/get/System/Boot-Manager-Disk/Check-Flash.shtml) and the USB drive passed without errors.

The corrupt mp3 file displays the strange behavior if I play the USB drive on either my car stereo or home PC, so I know it's the file and not the player.

I already checked that my USB flash drive is set to "optimize for quick removal" in Device Manager, meaning that I shouldn't have to use the "safely unplug hardware" link before unplugging the drive.

Does anyone know what could be causing this?

 

[pandemonium]

What file system is the flash drive formatted with? exFAT or FAT32?

What OS are you using?

Try creating a folder on the USB flash drive and dropping those files in there to see if it resolves the problem.

 

[Special K]

What file system is the flash drive formatted with? exFAT or FAT32?

FAT

What OS are you using?

Vista Business 64 bit

Try creating a folder on the USB flash drive and dropping those files in there to see if it resolves the problem.

This is actually what I have been doing all along. Each podcast was downloaded into it's own separate folder. The deleted file that started playing had actually resided in a different folder from the one that was originally playing and actually existed on the USB drive.

 

[VirtualLarry]

I already checked that my USB flash drive is set to "optimize for quick removal" in Device Manager, meaning that I shouldn't have to use the "safely unplug hardware" link before unplugging the drive.

I don't think that's true. I'm pretty sure you need to use SRH every time.

 

[Cerb]

I don't think that's true. I'm pretty sure you need to use SRH every time.

Yup, try that. Going to one that was deleted mid-stream just screams "FAT problem," like the XXL scooter buggies at Walmart (they're like 3x as big as other chains' scooter buggies these days, I swear...that, or it's just a bigger seat and 10x bigger people on them ).

 

[Special K]

I don't think that's true. I'm pretty sure you need to use SRH every time.

Then what's the point of having the option to "optimize for quick removal" if Windows is still caching the writes? I thought the whole point of that option was to make it so you could just unplug the USB drive (provided it wasn't right in the middle of an operation - i.e. the access light was blinking)

 

[Cerb]

Then what's the point of having the option to "optimize for quick removal" if Windows is still caching the writes? I thought the whole point of that option was to make it so you could just unplug the USB drive (provided it wasn't right in the middle of an operation - i.e. the access light was blinking)

You probably have needed to run chkdsk on it for awhile, now. It's FAT. You have to use FAT, most likely, but still, it's FAT. Never trust FAT to hold the only copy of anything, if you can help it. Also, pulling power if it is writing can present some risk of bricking (if the light's not flashing, that shouldn't be an issue). I don't always use the safely remove option, but I always do if it's a FAT device, because yes, corruption happens.

Optimizing for quick removal causes Windows to flush its buffers ASAP. With an internal drive, it could wait several minutes, especially if the drive is spun down. In that case, safe removal could take more than a split second to unmount (sometimes several seconds of grinding, for HDDs, since hot-swappable ones still get the 'performance' setting). OTOH, it can also safely write to the drive less, since it can delay updating metadata when copying many files, which can mean a big speed increase.

Now, why doesn't Windows just try to keep it ready to eject, most of the time, and give you an indicator? I'm guessing walled gardens inside of MS, because there's no way hundreds of separate MS employees haven't come up with some variation on that very idea, over the years.

 

[Special K]

You probably have needed to run chkdsk on it for awhile, now. It's FAT. You have to use FAT, most likely, but still, it's FAT. Never trust FAT to hold the only copy of anything, if you can help it. Also, pulling power if it is writing can present some risk of bricking (if the light's not flashing, that shouldn't be an issue). I don't always use the safely remove option, but I always do if it's a FAT device, because yes, corruption happens.

What makes FAT so much worse than any other filesystem? Why can't NTFS be used on USB drives?

 

[pandemonium]

NTFS can be used on most flash drives, but it's typically not due to it requiring more active reads/writes to the medium.

FAT was more universally accepted by multiple OSes, but now that has changed for the most part, so using NFTS wouldn't be a bad idea. Just expect that flash drive to wear a little sooner than if you were to use exFAT or FAT32.

As long as whatever devices you use the flash drive with can read NTFS, you're set.

 

[Cerb]

What makes FAT so much worse than any other filesystem?

If a partial write occurs, such that some new data as been written, but metadata not updated, how can you get a consistent state? You can't even really know for sure the problem, at least not all the time. With metadata journaling, the FS driver can at least know that files X, Y, and Z might be screwed up, if it doesn't read that they were written correctly, and/or that a clean unmount had occurred (in the best case, it can roll them back, but not always). Try to get in the habit of using the safely remove hardware feature.

Why can't NTFS be used on USB drives?

Does your car's radio, or your 3rd-party GPS, or cell phone, support NTFS? There's the rub. Every USB storage device comes formatted some kind of FAT, for near-universal compatibility.

 

[Special K]

If a partial write occurs, such that some new data as been written, but metadata not updated, how can you get a consistent state? You can't even really know for sure the problem, at least not all the time. With metadata journaling, the FS driver can at least know that files X, Y, and Z might be screwed up, if it doesn't read that they were written correctly, and/or that a clean unmount had occurred (in the best case, it can roll them back, but not always). Try to get in the habit of using the safely remove hardware feature.

Interesting. I never really knew the differences between FAT and NTFS until reading this thread. Here's a brief overview for anyone who is interested:

http://en.wikipedia.org/wiki/Journaling_file_system

Does your car's radio, or your 3rd-party GPS, or cell phone, support NTFS? There's the rub. Every USB storage device comes formatted some kind of FAT, for near-universal compatibility.

Good point. I might try an NTFS formatted drive in my car stereo just for the heck of it, but I suspect it won't work.

EDIT: D'oh, I looked up my stereo's spec sheet online and found this:

[4] USB playback not supported for NTFS formatted devices. When partitions are created, only the first partition can be read.

Looks like I'm stuck with FAT.

 

[fixbsod]

Was anyways else picturing the dos equis guy while reading this part...

But yes I also like to always use SRH.

I don't always use the safely remove option, but I always do if it's a FAT device, because yes, corruption happens.

 

[Cerb]

Was anyways else picturing the dos equis guy while reading this part...

Actually, I was trying to make the cadence work when composing it, but I couldn't come up with a way to end the sentence that worked.