ReadyNAS NV+ ate my WD20EZRX (2TB Green)?

Okay:

$ sudo -i
# hdparm --security-unlock NETGEAR 

/dev/sdb security_password="NETGEAR"

/dev/sdb:
 Issuing SECURITY_UNLOCK command, password="NETGEAR", user=user
SECURITY_UNLOCK: Input/output error

here's the dump of the disk info

# hdparm -I /dev/sdb

/dev/sdb:

ATA device, with non-removable media
    Model Number:       WDC WD20EZRX-00D8PB0                    
    Serial Number:      WD-WCC4M3RSE322
    Firmware Revision:  80.00A80
    Transport:          Serial, SATA 1.0a, SATA II Extensions, SATA Rev 2.5, SATA Rev 2.6, SATA Rev 3.0
Standards:
    Supported: 9 8 7 6 5 
    Likely used: 9
Configuration:
    Logical        max    current
    cylinders    16383    16383
    heads        16    16
    sectors/track    63    63
    --
    CHS current addressable sectors:   16514064
    LBA    user addressable sectors:  268435455
    LBA48  user addressable sectors: 3907029168
    Logical  Sector size:                   512 bytes
    Physical Sector size:                  4096 bytes
    device size with M = 1024*1024:     1907729 MBytes
    device size with M = 1000*1000:     2000398 MBytes (2000 GB)
    cache/buffer size  = unknown
    Nominal Media Rotation Rate: 5400
Capabilities:
    LBA, IORDY(can be disabled)
    Queue depth: 32
    Standby timer values: spec'd by Standard, with device specific minimum
    R/W multiple sector transfer: Max = 16    Current = 16
    DMA: mdma0 mdma1 mdma2 udma0 udma1 udma2 udma3 udma4 udma5 *udma6 
         Cycle time: min=120ns recommended=120ns
    PIO: pio0 pio1 pio2 pio3 pio4 
         Cycle time: no flow control=120ns  IORDY flow control=120ns
Commands/features:
    Enabled    Supported:
       *    SMART feature set
       *    Security Mode feature set
       *    Power Management feature set
       *    Write cache
       *    Look-ahead
       *    Host Protected Area feature set
       *    WRITE_BUFFER command
       *    READ_BUFFER command
       *    NOP cmd
       *    DOWNLOAD_MICROCODE
            Power-Up In Standby feature set
       *    SET_FEATURES required to spinup after power up
            SET_MAX security extension
       *    48-bit Address feature set
       *    Device Configuration Overlay feature set
       *    Mandatory FLUSH_CACHE
       *    FLUSH_CACHE_EXT
       *    SMART error logging
       *    SMART self-test
       *    General Purpose Logging feature set
       *    64-bit World wide name
       *    WRITE_UNCORRECTABLE_EXT command
       *    {READ,WRITE}_DMA_EXT_GPL commands
       *    Segmented DOWNLOAD_MICROCODE
       *    Gen1 signaling speed (1.5Gb/s)
       *    Gen2 signaling speed (3.0Gb/s)
       *    Gen3 signaling speed (6.0Gb/s)
       *    Native Command Queueing (NCQ)
       *    Host-initiated interface power management
       *    Phy event counters
       *    NCQ priority information
       *    unknown 76[15]
            DMA Setup Auto-Activate optimization
            Device-initiated interface power management
            Software settings preservation
       *    SMART Command Transport (SCT) feature set
       *    SCT LBA Segment Access (AC2)
       *    SCT Features Control (AC4)
       *    SCT Data Tables (AC5)
            unknown 206[12] (vendor specific)
            unknown 206[13] (vendor specific)
            unknown 206[14] (vendor specific)
Security: 
    Master password revision code = 1
        supported
        enabled
        locked
    not    frozen
        expired: security count
        supported: enhanced erase
    Security level high
    282min for SECURITY ERASE UNIT. 282min for ENHANCED SECURITY ERASE UNIT.
Logical Unit WWN Device Identifier: 50014ee20b408fd5
    NAA        : 5
    IEEE OUI    : 0014ee
    Unique ID    : 20b408fd5
Checksum: correct

I tried attaching the other disk back into the ReadyNAS. It acknowledges the insertion event, but then goes into CPU starvation: ssh won't respond, and the web UI won't load fully.