The accident reportedly took place on Wednesday after a routine Freeview update rejigged its programme guide.
All children’s channels are said to have been moved to 201-229, taking the regular spot of the adult listings.
Although the X-rated programmes have also had a change of location, moving to 670-699, viewers who hadn’t updated the service would see both genres bundled together.
Parents were angry by the mix-up, with mother-of-two Danielle, of Lincoln, telling The Sun: “I went to put CBeebies on for my four-year-old son on channel 121 as usual and there was a message saying that it had moved to 202.
“My remote doesn’t work properly so I couldn’t punch in 202 and instead had to press the up button to go through the channels to 202.
“As I got closer to 200 I realised I was going through the adult channels. I was horrified my son would see something inappropriate,” she explained.
More took to Twitter to comment on the incident, with one posting: “So Freeview have moved cbeebies channel right in the middle of all the smut channels. LG don’t have a delete channel ‘service’.”
Another agreed, posting: “Ooh, free view has updated the @YouView box so now you have to scroll past all the adult channels to get to CBeebies. Odd decision.”
A spokesperson for Freeview has since addressed the incident, telling the newspaper: “If someone goes to that channel there is no adult material being broadcast. All they will see is a message explaining that genre has now moved to a new channel.
“On some TVs that haven’t been retuned they may still appear at the old channel numbers. Retuning will restore the correct channel line-up. “