I have broadband cable with good reception and until recently, no issues - but in the last couple of weeks after about 20-30 minutes of use, I lose the TV picture with the TV screen just saying "no signal". Occasionally, whilst in its in this state, I can still press the red button to get text news, but after a further 5 mins or so, the text goes too, leaving just the black screen with "no signal" message.
I've switched off and on/rebooted, checked cable connections etc. Finally, I replaced the high speed HDMI cable with a scart lead from the set-top box to TV and all is well.
However, that just leaves me with the suspicion that either the HDMI cable is faulty (but why would the fault occur after 20 mins of use, or, more likely, that something within the box is going. Box and HDMI cable are only about 6 months old - so, Virgin tech squad, is it the box that needs replacing?