I can't get purchased HD Instant Video rentals to download and play correctly on my Tivo HD (model 652). I rent and initiate from the Amazon web site. SD videos download and play fine. HD videos start downloading but either the download speed is ridiculously slow or it stalls completely, although in one case a 2-hr movie downloaded in 4 hrs -- but it stalled during playback just 15 mins into the video and there was no way to play the rest of it. This same movie, on a retry, was still downloading after 12 hrs upon which it quit and the message in the To Do Recording History said someone at my end cancelled it (not true). I've tried several HD downloads and they all exhibit the same issues. I've unregistered and re-registered my Tivo -- no change. My TiVo is on wired ethernet that tests greater than 10 Mbps download speeds. I have a BR player that can stream these same videos even over WiFi with no problem. I've restarted the TiVo. I have 11.0m software now and the problem was the same with 11.0k. Amazon wants me to reboot my router and then call them (again) if I still have problems. They claim to have great diagnostic tools they can apply to this problem -- but not til I reboot the router. So I'll do that ..... then test their great diagnostic powers.