Well, the response to the ticket was quite fast :
https://status.online.net/index.php?do=details&task_id=720
Here's the stated cause :
>Our tests have confirmed an issue caused by the fans of the power supplies installed in several chassis.
>The fans create vibrations amplifying errors on the discs.
Now on to decide whether I'm waiting for the fix or re-building a new box...
Thanks a bunch for your help.
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Bien à vous, Vincent Veyron
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