Yes the program I was thinking of was Potsworth & Co. (known as Midnight Patrol: Adventures in the Dream Zone in the US).
The premise of the program involved a group of friends, who when they went to sleep, entered the Dream Zone and had to help protect it against the Nightmare Prince. Whilst in the Dream Zone each of the kids had a special power, such as Potsworth the dog who could talk and Nick who became Super Nick and could fly. There is also The Grand Dozer who is the King of the Dream Zone and is always atop a pile of mattresses. He is always half-asleep because if he fully wakes up the Dream Zone will end. I never wondered it as a child but I bet if it was a pile of memory foam mattresses he wouldn’t be able to help but fall asleep. But if he did that the Dream Zone would end. And that wouldn’t make a very good TV show now would it?
Anyway, check out the catchy intro:
