I know this thread is very old, but does anyone have the latest firmware for the LC-46D92U? I've been pulling my hair out trying to get power on to work over RS-232 (via Crestron). I've done everything in this thread and have had no luck (including sending RSPW1 and it's varation ...which all return OK). After sending the power off command, the entire RS-232 I/F is disabled and doesn't respond to any further commands ("POWR? " or otherwise). I'm then forced to use IR to turn the system back on. I have version 1.11, but the Sharp tech support claims there has never been a firmware upgrade.