Tech Note: Flash Memory Random Remix

The micro-SD flash memory chip that came with my new smartphone has some interesting issues with data integrity. I mostly use it to store sound files in the mp3 format, both pop songs of a few MB each and podcasts taking up tens of megabytes. And while listening to podcasts, in the middle of them, I have repeatedly come across three interesting and disturbing errors. The flash memory makes psychedelic remixes of my sound files!

  1. As I listen to one mp3 file, I suddenly hear several seconds from another file before the original recording resumes.
  2. As I listen to one mp3 file, I suddenly hear several seconds from a deleted file before the original recording resumes.
  3. As I listen to an mp3 file, the audio suddenly becomes pitched down to a barely comprehensible guttural grunt for tens of seconds.

These changes to the original files are permanent and always recur in the same way. With audio files, it's mainly just a nuisance. But there was GPS map data delivered on that chip too. I don't think it would be very useful after spontaneous random remix with snippets of mp3 audio.

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The first two sound like an addressing problem but the third sounds more like a problem with the audio codec (unless the data read access is totally farked up). The simple test would be to swap memory modules.