My guess is that this issue has not been experienced yet since you are dealing with a new TC with a new window design. Its probably one of those minor problems that slipped by the factory and will not be addressed until they get some feedback from owners. Over the past 3 years Ive seen Northwood confront and address several issues that were brought to their attention by owners so Im sure they will find a solution to this one in time. It might be a good idea to call and let the factory know what you are experiencing. They might have a fix or suggestion for it already.