Tivo S2 with wired USB - much slower than Dual Tuner

[AbMagFab]

It seems like it's using USB 1.x, not 2.x. Anyway to upgrade it? I'm getting about 1/10th the transfer speed from my single-tuner Tivo as from my dual-tuner Tivo's (to/from each other and my computer). All on a hard-wired gigabit backbone.

Any thoughts? Are the USB drivers just super slow?