We have three (presumably) identical sony STB's attached to three separate TV's all driven by boosted signals from a labgear dist amp.
Last night ONE, and only ONE was giving either 'no audio/video or a red screen announcing that yes, you had BBC4, but it wasn't actually on.
The other two were showing the Copenhagen film.
All showed 100% signal level and quality.
By going into the manual tune section, I was able to pull BBC4 up on channel 39..
I selected it, and then on exiting the menu, but not before, finally normal service was resumed.
I cannot for the life of me puzzle this one out...anyone got any ideas?