I am a firmware engineer - my job is to code up the software that runs on these devices. I can tell you there is no justification for constantly popping messages like "LCN has changed" and "Do you want to search" up over the programme material the customer is trying to watch. This is cripplewear, added at the demand of the business managers, who are under pressure to reduce the usefulness of the low-price product. The thing is, the chipset for freeview is very cheap, such that a basic set-top-box never needs to cost more than £15 or so. But the sellers want £50+ and so they build deniable faults into the lower-priced units to force people to upgrade. To avoid returns and refunds, they make the faults ambiguous so that customer service can keep on saying "just restart it", "click A then B" and so on, kicking the issue into the long grass. It's a cynical game, and you should complain strongly to the outlet that sold the unit to you.