Yeah, if it was affecting just the USB side I'd be inclined to blame USB stupidity (especially if there's an ASMedia USB chip involved). But since it seems to be affecting eSATA as well, it is most likely an issue with the dock itself, or the power brick.
FWIW I own the dual-bay version of that dock. I experienced issues similar to the one the OP is reporting when I connected via one of the above mentioned ASMedia USB interfaces, but it seems OK when connected via eSATA or a non-ASMedia USB port. (Well, aside from the fact that you can't individually hot-swap the two bays, since inserting a drive into one bay apparently resets the drive in the other bay... but that's a separate issue.)
Nostalgia isn't what it used to be.