Miele Powerline C3 Vacuum Cleaner Starts/Stops by iteself

I have a powerline C3 Miele which was working fine for 5 years. It suddenly has started a strange behaviour, which makes it unusable! WhenI swtich on it cuts out/ switch off after 10 seconds being on, then after few seconds it switches back on for another 10 seconds and it goes on like this (left it for 5 min or so, still does the same thing). I replaced all the filters, checked for any blockage (except inside the motor) and do not know what is is the problem? Anybody had similar issue with their machine??