RS5 DSG Question?

When in Sport mode with the shift lever or using Dynamic mode my DSG hangs up in 3rd and 4th gears at as high as 4000 rpm despite extremely small throttle angles as well as removing my foot from the throttle entirely in an attempt to get an up shift. Only way to get an up shift is going back to drive or using manual mode to move it up a gear. Is this normal in these modes?
Thanks.