Why do my headphones contain a valid storage medium?

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austanss
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Why do my headphones contain a valid storage medium?

Post by austanss »

Slightly off-topic, but OS developer expertise would be useful here.

I have a pair of Bluetooth headphones that charge via microUSB. I plugged them in to my computer to charge them. Shortly thereafter, a 16 MB storage medium shows up in my file manager. I tested this and it occurs in both Linux and Windows.

The crazier part, though, is that it is a valid (read-only) partition. The filesystem is VFAT, and it has one file located on it named “START.HTM”. This file contains 0 bytes of data, and its size is thus listed as 0 bytes.

Even weirder, it won’t show up in any partition managers. It seems to be a raw VFAT medium with no partition table. It’s contents are listed clearly in a file manager, and I can open the lone HTM(L) file (read-only) in any program.

The model is MPOW HC5. This isn’t a problem in any sense, but it’s curious. If I could somehow make the medium writable, assuming that it’s not a hardware ROM, it would be a very sneaky place to store small secret files.

It doesn’t seem that this would occur on accident. Someone had to design this thing to have a valid VFAT filesystem with a valid file entry. Any ideas?
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nullplan
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Re: Why do my headphones contain a valid storage medium?

Post by nullplan »

There are a bunch of devices that connect to USB and mime a mass-storage device at first. In your case, maybe all the time, since the primary function of the device is not accessed via USB. I have a UMTS modem (that I can probably throw away now that UMTS has been turned off), which will claim to the uninitiated OS that it is a USB CD drive. It will switch to its main function only after receiving a bespoke command sequence.

Main purpose of such a thing normally is to distribute the drivers. Miming an optical drive is done normally to get Windows to auto-play, though I think they disabled that after it was found out that the data for the disc, being stored on a flash ROM, could be overwritten (e.g. by viruses). I'm guessing in your case the data got lost somehow.
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