Can't seem to turn off write caching.

~
dt1:sudo hdparm -I /dev/sdc1

/dev/sdc1:
SG_IO: bad/missing sense data, sb[]:  70 00 05 00 00 00 00 0a 00 00 00 00 20 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00

ATA device, with non-removable media
	Model Number:       ��+@�Z#��C����`@�������`�O�@�_�@��=�����
	Serial Number:      i`�ih���I@�k= �l��
	Firmware Revision:  ����퉠
��      Media Serial Num:   Ơ��K���`��,���|�
  ���`
	Media Manufacturer: ���Š��
��`���
	Transport:          Parallel; Revision: 0xf4bb
Standards:
	Used: unknown (minor revision code 0xf35e) 
	Supported: 12 10 
	Likely used: 12
Configuration:
	CHS addressing not supported
	LBA    user addressable sectors: 4085503040
	Logical  Sector size:            3431065366 bytes
	Physical Sector size:            3431065366 bytes
	device size with M = 1024*1024: 13368250701391 MBytes
	device size with M = 1000*1000: 14017626847461 MBytes (14017626847 GB)
	cache/buffer size  = unknown
	Nominal Media Rotation Rate: 62291
Capabilities:
	LBA, IORDY(may be)(cannot be disabled)
	Queue depth: 13
	Standby timer values: spec'd by Standard, no device specific minimum
	R/W multiple sector transfer: Max = 129	Current = 94
	Recommended acoustic management value: 68, current value: 32
	DMA: *mdma0 *mdma1 mdma3 *mdma4 *mdma5 *mdma6 *mdma7 (?)
	     Cycle time: min=62312ns recommended=57024ns
	PIO: pio0 pio1 pio2 
	     Cycle time: no flow control=62367ns  IORDY flow control=41600ns
	   *	reserved 69[2]
	   *	reserved 69[3]
	   *	reserved 69[4]
	   *	reserved 69[6]
	   *	DOWNLOAD MICROCODE DMA command
	   *	SET MAX SETPASSWORD/UNLOCK DMA commands
	   *	DEVICE CONFIGURATION SET/IDENTIFY DMA commands
	   *	Long physical sector diagnostics
	   *	CFast specification support
	   *	Data Set Management TRIM supported (limit 62355 blocks)
	   *	Deterministic read ZEROs after TRIM
		Removable Media Status Notification feature set supported
Security: 
	Master password revision code = 34944
	not	supported
	not	enabled
	not	locked
	not	frozen
	not	expired: security count
		supported: enhanced erase
Integrity word not set (found 0xf371, expected 0x88a5)
SG_IO: bad/missing sense data, sb[]:  70 00 05 00 00 00 00 0a 00 00 00 00 20 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
Device Sleep:
	DEVSLP Exit Timeout (DETO): 20 ms (default)
	Minimum DEVSLP Assertion Time (MDAT): 10 ms (default)
~
~
dt1:sudo hdparm -W /dev/sdc1

/dev/sdc1:
SG_IO: bad/missing sense data, sb[]:  70 00 05 00 00 00 00 0a 00 00 00 00 20 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 write-caching = not supported
~
~
dt1:sudo hdparm -W0 /dev/sdc1

/dev/sdc1:
 setting drive write-caching to 0 (off)
SG_IO: bad/missing sense data, sb[]:  70 00 05 00 00 00 00 0a 00 00 00 00 20 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
SG_IO: bad/missing sense data, sb[]:  70 00 05 00 00 00 00 0a 00 00 00 00 20 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
SG_IO: bad/missing sense data, sb[]:  70 00 05 00 00 00 00 0a 00 00 00 00 20 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
SG_IO: bad/missing sense data, sb[]:  70 00 05 00 00 00 00 0a 00 00 00 00 20 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
SG_IO: bad/missing sense data, sb[]:  70 00 05 00 00 00 00 0a 00 00 00 00 20 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 write-caching = not supported
~
dt1:sudo hdparm -W /dev/sdc1

/dev/sdc1:
SG_IO: bad/missing sense data, sb[]:  70 00 05 00 00 00 00 0a 00 00 00 00 20 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 write-caching =  1 (on)
~
I also tried with /dev/sdc,  
~
dt1:sudo hdparm -W0 /dev/sdc

/dev/sdc:
 setting drive write-caching to 0 (off)
SG_IO: bad/missing sense data, sb[]:  70 00 05 00 00 00 00 0a 00 00 00 00 20 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
SG_IO: bad/missing sense data, sb[]:  70 00 05 00 00 00 00 0a 00 00 00 00 20 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
SG_IO: bad/missing sense data, sb[]:  70 00 05 00 00 00 00 0a 00 00 00 00 20 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
SG_IO: bad/missing sense data, sb[]:  70 00 05 00 00 00 00 0a 00 00 00 00 20 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
SG_IO: bad/missing sense data, sb[]:  70 00 05 00 00 00 00 0a 00 00 00 00 20 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 write-caching =  0 (off)
~
dt1:sudo hdparm -W /dev/sdc

/dev/sdc:
SG_IO: bad/missing sense data, sb[]:  70 00 05 00 00 00 00 0a 00 00 00 00 20 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 write-caching =  1 (on)
~