To get things clear.
Option 0 Audio or Video shuts down the ir-reception, nothing more.
Option 1, Each audio or video device reacts to it own commands
Option 2 This makes the video OR the audio a Master device. Video option 2, then Audio in option 0 (when linked and speakers attached to the Video device). Audio Option 2, then Video in option 0 and speakers connected to the audio device.
Option programming is done in stand by and confirmed by the flashing once by the red dot led.
Option via Beo4 => VOpt or Aopt(under Standy and List simultainiously, then config), then press optionnumber
Option BL 1000, choose ,sound, store, optionnumber, store (for audio option programming)
Option BL 1000, choose, picture, store, optionnumber, store (for video option programming)
Putting the MX 5500 in option 0 sets the ir reception to off and so the DVD1 MKI or II, will not respond.