Iv already tried this to no avail!
Like I said no pic but sound, then after a while I left the x box running and watched TV for a while, then when I went back to the x box channel it was working! Tried doing the same again but it didn't work, I think in the 3 weeks iv had it its worked about 4 times but there's not set way it comes on, its just when the bloody thing feels like it!