Ceed has strange starting problems

Hello, I have a Ceed Bj 2009 since October 2011. He always has a Macke, which no one has repaired so far: sometimes he starts nciht. He then rattles, but somehow does not ignite. Sometimes he can be persuaded, if you give gas to it, but sometimes not and I need 10 attempts until he decides to start. Then he is also full. In general he spins when the radio was still on or the climate, then he usually doesn’t make it. The whole is mi r since the purchase happened about 20 times. It is not dependent on temperature (in summer as in winter) and also not on the service life (sometimes happens 2 times a day). In the workshop the battery contacts have been cleaned and oiled, because this is probably a known Ceed problem. However, the problem still occurs. The battery itself is by the way i.o. In the large 40,000 inspection in November one did not mention my problem, one has found allegedly nothing. Yes, the problem occurs j a never on when a mechanic is watching Do you have an idea what it could be? Does that pay for the great Kia guarantee? Oh yes, for a while I even had the feeling he’s going to kneel at the intersection when I’m standing and the climate and the radio are on at the same time.