Problem with iZotope RX8.0/8.1 - only takes a small section

Nuendo 11:
I’m trying to edit an 18 minute dialogue, but the iZotope RX8 (Advanced) Editor only takes 3 minutes from the clip.
As usual, I use the Connect plugin in the DOP. But the editor only opens a small section of the material of 3 minutes - instead of 18 minutes. This happens with every clip. Only 3 minutes are loaded at a time.
I updatet RX8.0 to RX8.1 - same problem.

Does anyone have a workaround - or does it work for someone?
I didn’t had this in Nuendo 10.3

Windows 10x64 / Nuendo 11 / iZotope RX8.1