Media errors Power Edge 2800

Hi,

I have a Power Edge 2800, with a RAID 5 (4 disks), one of the disk failure, and two had failure prediction, and were replaced and rebuilt one by one, the optimal stay RAID, however one of the replaced disk failure again, and check the status of all these by the controller, Objects - Physical drives - F2, recorded media errors, confirm with the diagonstics of 32 BITS, is that errors in the new drives? or something else, I updated the firmware and drive, BIOS, BMC, but the result is the same, what is failing, any ideas?

Thanks

BS