Looks like this drive
ata12.00: ATA-9: WDC WD80EZZX-11CSGA0, VK0J335Y, 83.H0A03, max UDMA/133
is continually resetting
Mar 7 19:20:06 MEDIASERVER1 kernel: ata12.00: failed command: READ FPDMA QUEUED
Mar 7 19:20:06 MEDIASERVER1 kernel: ata12.00: cmd 60/40:40:20:e8:0c/00:00:05:00:00/40 tag 8 ncq dma 32768 in
Mar 7 19:20:06 MEDIASERVER1 kernel: res 40/00:00:20:e8:0c/00:00:05:00:00/40 Emask 0x10 (ATA bus error)
Mar 7 19:20:06 MEDIASERVER1 kernel: ata12.00: status: { DRDY }
Mar 7 19:20:06 MEDIASERVER1 kernel: ata12: hard resetting link
Mar 7 19:20:12 MEDIASERVER1 kernel: ata12: link is slow to respond, please be patient (ready=0)
Mar 7 19:20:16 MEDIASERVER1 kernel: ata12: COMRESET failed (errno=-16)
Mar 7 19:20:16 MEDIASERVER1 kernel: ata12: hard resetting link
Mar 7 19:20:17 MEDIASERVER1 kernel: ata12: SATA link up 3.0 Gbps (SStatus 123 SControl 300)
Mar 7 19:20:17 MEDIASERVER1 kernel: ata12.00: configured for UDMA/133
Mar 7 19:20:17 MEDIASERVER1 kernel: ata12: EH complete
Odds on caused by bad / loose sata cabling to the drive or the p/s connector to the drive. Reseat everything.
Just be aware that SATA cables by their very design are garbage, and it is quite possible that when you reseat or change this one that you will disturb another and cause the same issue on a different drive. Be careful