AEG Lavatherm motor hums 2-3 secs, then stops?

Hello, when I switch on my AEG Lavatherm 56800 condenser dryer the motor starts humming for two, three seconds but then stops. This happens in any program. After having opened the dryer I don't think there is a mechanic fault with the belt. Also, there is no sign of burning and no smell. Pushing the drum whilst the motor is humming does not help. Could it still be the starting capacitor? What else could I try? Thank you very much.

The numbers inside the door are:
91A AD AB 10A
PNC 916 012 12800
S-No 53816093