Only times it happenned to me was a few weeks ago, after trying to use the Koss Porta Pro for my walk home(1h20 more or less) that I usually do with IEMs. Because there's a river that runs alongside the path and has quite a fast flow depending on the time of the year and weather, it can get very noisy to the point you have to almost scream to have a conversation with someone else, and thus without even noticing I pushed the volume too much to cover the noise of the river ...

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The high pitched noise in my ears took about 48 hours to finally completely disapear ... Lesson learned, only gear that isolate well for the walk home from now on ...