We also have a V6.but this fault occurred on the earlier Tivo. It gave the 25% message after it came back on after a power cut. After 4 days my partner cleared the fault and details are vague. She says that she used the TV remote and it came on using input AV1 showing what I guess are the built in Freeview channels. Later she used the TV remote to select AV4 for Virgin channels and they were there again! Did not touch any connections.