Thanks for using the forums to get this issue looked into with your sound on ITV channels, I understand how frustrating this must be for you and I am sorry. I am aware its been some time since you posted about this so if the issue has been resolved just let me know 🙂
If the issue is still persisting can you -
Tell me if it happens on live ITV or On demand?
What box do you have, V6 or TIVO?
Can you do a reboot on the back of the box, not at the mains.