If I power on my Sony TV & STB together, the remote control (P265) does not work at all - for the 1st 5 minutes. After about 5 minutes (seems like an eternity) the remote works fine. But if I turn the STB on 1st, then select whatever channel I want to watch (if I know), then turn the TV on, I can watch that channel. But I still can't change channels or use the menu. This happens EVERY TIME! What causes this behavior?
This sounds like the classic IR interference problem where IR radiation emitted by your TV blocks the IR signal of the remote. There are many threads on this forum, so search for the background and see solutions implimented by others. I had this problem, too, and found several things helped. Make sure the TV is in a normal viewing mode and not in the out-of-box mode of "vivid" or some such. These super contrast/super bright modes are used by stores for display because people think "bright" is "better". They do use more power and emit more IR. Also, when a TV is first activated is when the IR is highest as it ramps up to operating speed. Another thing to try is relocate the STB away from the TV. or place shelves and other itmes between it and the TV. You want to block or shield the STB somehow - I ended up making a nonflammable screen to shield or hood the STB. You might also disable any room light sensing routine your TV might use to adjust itself. Good luck.