Given that you get the same problem with the Beo4 and Beo5 means that it is not a programming issue with the Beo5.
With regards to the STB-C software version can be viewed from the "Service Menu" Press MENU on the Beo4, then SETUP then 0 0 GO
As the STB is not turned off by pressing the RED standby button then this almost certainly means:-
- You are using a Motorola model type from the STB-C which is not exactly the same as what was selected.
- The STB-C software for that model has been incorrectly programmed for that Motorola model
Provided the Motorola STB is in "line of sight" of your Beo5, then the Beo5 can be programmed to send the command bypassing the STB-C
What is the model number of the Motorola STB ?
All Motorola STB's use the NEC protocol, so it is very easy to programme or modify the XML file for it.