Ubuntu 14.04 blk_update_request I/O error on same sector across all drives with ZFS

I'm running Ubuntu 14.04 with ZOL version v0.6.5.4:

root@box ~# dmesg | egrep "SPL|ZFS"
[   34.430404] SPL: Loaded module v0.6.5.4-1~trusty
[   34.475743] ZFS: Loaded module v0.6.5.4-1~trusty, ZFS pool version 5000, ZFS filesystem version 5

ZFS is configured in raidz2 across 6x 2TB Seagate SpinPoint M9T 2.5" drives, with a read cache, deduplication and compression enabled:

root@box ~# zpool status -v
  pool: bigpool
 state: ONLINE
config:

        NAME                                           STATE     READ WRITE CKSUM
        bigpool                                        ONLINE       0     0     0
          raidz2-0                                     ONLINE       0     0     0
            ata-ST2000LM003_HN-M201RAD_S37<redactedid> ONLINE       0     0     0
            ata-ST2000LM003_HN-M201RAD_S37<redactedid> ONLINE       0     0     0
            ata-ST2000LM003_HN-M201RAD_S37<redactedid> ONLINE       0     0     0
            ata-ST2000LM003_HN-M201RAD_S37<redactedid> ONLINE       0     0     0
            ata-ST2000LM003_HN-M201RAD_S37<redactedid> ONLINE       0     0     0
            ata-ST2000LM003_HN-M201RAD_S34<redactedid> ONLINE       0     0     0
        cache
          sda3                                         ONLINE       0     0     0

Every few days, the box will lock up, and I'll get errors such as:

blk_update_request: I/O Error, dev sdh, sector 764218200
blk_update_request: I/O Error, dev sdf, sector 764218200
blk_update_request: I/O Error, dev sde, sector 764218200
blk_update_request: I/O Error, dev sdd, sector 764218200
blk_update_request: I/O Error, dev sdc, sector 764218432
blk_update_request: I/O Error, dev sdg, sector 764218200

smartctl shows that the disks are not recording any SMART errors, and they're all fairly new disks. I find it odd too that they're all failing on the same sector (with the exception of sdc). I was able to grab a screenshot of the terminal (I can't ssh in once the errors start):

console errors

Perhaps this is a controller failing, or a bug related to zfs?