I have a Siemens X300PE that will not stay in standby mode. When I press the power button and select standby, I wait the required 20 seconds, or more, then when I pull the plug it shuts down in about 5 seconds as if, well, the plug had been pulled. I've changed the battery twice, the AC/DC Power supply and reloaded system software and restored the backup. Any thoughts on a cause?
