Repeatedly reads only first block

[JohnnyMarauder]

Trying to recover old DDS-90 tapes on a Sony DAT drive. Keeps reading only the first 32K block. I let it run on a tape and stopped it when the first 40+ .dd files were identical. Tried a couple others and get either this or it just keeps increasing the test size and never reads a block.

Installed fresh Ubuntu 20.x and kept using apt-get until it ran.

[bitsgalore]

Could it be the tape was written in variable block mode? If yes, tapeimgr doesn't support this (yet), see:

#28

(BTW only seeing this issue now, as for whatever reason Github didn't send me a notification!)