Keep getting blank disks when dumping 1.44MB 3.5" floppies

[floppydumper]

I've got a Panasonic JU-256A and a Samsung SFD-321B I've been using to dump a bunch of old games on 3.5" floppy. The 720k (not high density) disks seem to dump fine with both drives, but whenever I dump a 1.44MB disk I seem to get worthless data on both drives. Running samdisk in scan mode indicates that all cylinders are blank on both heads. Similarly, I tried writing back one of the images and reading it on another drive, and Windows said the disk isn't formatted.

I've verified that the source disk is, in fact, not blank. I put it into my little 3.5" USB drive and it listed the files, sizes, etc.

I'm dumping using the 1.44MB option in "Preservation" mode. Hardware is v1.1, firmware is v1.2. Software is v1.90, with automatic updates enabled.

What am I doing wrong?

Edit: Whoops...the Density setting was forced to "Low" for reads. Changing it to "High" produces the expected results. I'll leave this here in case anyone else makes the same mistake.

[admin]

Yep, I would have suggested checking the density setting. That actually enables different electronics in the drive for reading/writing in high density mode.