Zanussi Jetstream 1450 selector knob advances unaided?

My washer model fjs 1597w advances slowly through all settings without anything happening. Each time it passes a letter, the program seems to start, but then advances on within 5-6 seconds.Have tried starting the machine on different progammes, but still same problem.It is very cold where the machine is kept, could the outlet hose be frozen inside the machine? any help gratefully received.