The 540 units are slower, but with the USB200M adapter you should be seeing speeds a lot faster then that. Try doing a hard reboot on the TiVo by pulling the plug, allowing it to sit for a minute and then plugging it back in. Also, as Mark was suggesting, try pausing the TiVo on a program in Now Playing before starting the transfer. This frees up a little bit of resources on the TiVo by stopping the playback portion of the software, which in turn can make the transfer a little faster. Another suggestion to squeeze a little more out of it is to tune the TiVo to a channel you do not actually recieve so that it displays the blue "no signal" screen. This frees up the resources for the recording portion of the software and gives a little bit more to the transfer.
If none of that helps then you either have a faulty USB adapter or a problem with your network. One thing to check for is to make sure your network is running in 100Mbps mode. Some equipment out there still runs at the 10Mbps mode and if you have a hub or router which is only rated for the slower speed it will drag down the speed of your entire network.
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