Thank you Razlaw, Stefan, Nicky, Whlerz and Piet for helping out! Much appreciated.
I'll look into the customer service menu, and will try to delay the curtains long enough for the picture.
I don't have a sky box, I am just using B&O's built-in DVB module for the freeview channels - which is why I presumed it would all have been timed to work properly, as there is no point in designing the elctronic curtains if the effect is spoiled by the picture not being ready! Not very B&O!
It is interesting that the BV7 does this too when using the DVB...
I'll see if I can delay the curtains today. Will let you know.
Thanks again for your help guys,
Tom