I have a 6mt, I see 40s all day, even as high as low to mid 50s on several occasions. The dsg won't match it but u should at least be getting close to 40, if not mid 40s. I've read posts from others with the dsg hitting those figures.
Dumb question, but have you checked tire pressure too?
Would be worth checking for a sticking brake caliper.
Also, how many miles does the car have? I noticed my best tanks after I hit the 30k mark.
Lastly, any cel? Have you done a scan with vcds?
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