Pro line blue faces????

Hi all , my mates daughter has a proline all in one from comet and after i set it up last week he has phoned to say all the picture subtitles etc have a blue tinge even the text. My mate says that sky and the tv etc are all ok. If was set to rgb and was looped through the sky box on rgb. Everything was ok when i left, he's going to change the scarts so it's direct to the tv today to check it's not the sky box. Has anyone any ideas?????

Cheers.