It is not the round inside or outside (on the door) rubber seals that make the creaking noise, it's the plastic strip and felt area adjacent to. Red arrow marks the culprit
Wipe clean first, then apply Gummipfledge. Worked on my E39, works on my DCT. This solution lasts many months in most cases.
Just rag and soap to that area should give some temporary relief by the way. The Gummipfledge lasts much longer.