Based on my personal experience after a reset several months back, I can testify that one reason for not getting a clock and channel linup overnight in spite of forcing your Sony to the digital host channel is that if it reboots during the download that would normally produce a valid channel linuep, you end up back with no clock nor channel lineup. I could suggest you stay up all night watching your Sony for the "Welcome" message that comes up after a reboot, but maybe you should try one of these:
a) Set up a video recorder to watch your Sony overnight for the telltale reboot (stop-motion, 1 frame per second is ok and will save a lot of memory/tape.)
b) Disable auto power off, run the G* test while tuned to your digital host channel, and keep an eye on the Sony for a couple hours for a reboot. This process accelerates the attempted download of channel lineup and will usually precipitate a reboot within a couple hours if one is going to happen at all.
If, as I did, you notice it rebooting every night or during the G* test, you need to use another zip-code to complete the channel lineup download, as the one for your current zip-code is overflowing some sort of internal buffer in the Sony and causing the reboot (and thus getting you nowhere.) Try changing your zip-code to a distant suburb maybe 40 miles or so away that is likely to receive the channels you are interested in but not as many as your current zip-code does. In the Philadelphia area, I've found that 19601 for Reading, PA does the trick and eliminates the rebooting during channel-lineup downloads.
For more background on this "feature", see http://www.avsforum.com/avs-vb/showt...4#post15209864
As always, this may not be your problem... but it has helped me and several others get past this point.