Comment by sumtechguy

That is not terribly surprising. The cheap tape drives of that era were very picky like that. Even if I had the same tape drive as a friend it was not always certain that I could read back my tape on his box and the other way around. These drives were very affordable and the tapes were low priced as well. However, they were really designed for the 'oh no I messed up my computer let me restore it' or 'I deleted a file I should not have' scenarios. Not server side backup rotation solutions. Unless that was the backup/restore computer. Long term storage or off site type drives were decently more pricy.

My guess is they lack the RAM buffer and CPU to properly keep up correctly. Then with a side of assumptions on the software side.