I just found that the Cambridge is the Oppo 971H (not 970-HD as I first thought).
And in the Oppo 971H faq, I just read:
Q: Is there a firmware update that will add discrete on/off remote codes to the OPDV971H so that I can use my universal remote control to turn on/off all my AV equipments at once?
A: Due to existing hardware limitation, it is impossible to add discrete on/off to the current OPDV971H via a firmware update. The reason is that the 971H hardware was designed to have a "true standby" mode. When the power is turned off using either the remote or the power button on the player, the entire DVD player shuts down. The main processor which is in charge of interpreting the remote code is turned off completely. The only circuits with power are the standby power supply and the IR sensor board. The IR sensor board can only interpret one remote code, which is the current ON/OFF code. When it receives this code, it turns on the main power supply thus bringing the player out from standby mode. Because the main processor is turned off in the standby mode, it is impossible to interpret a discrete on/off remote code with it.
