I don't use the DC on my bandsaws
I use a shop vac on my 14" and 18" bandsaws, and I put the collection nozzle right under the table where the saw dust is generated. The shop vac has a much higher velocity air stream than the DC and so it works better to collect the fine dust generated by a bandsaw. I use the DC for the dual drum sander, thickness planers, jointer and table saw all with the 4" ports.
The answer to your question will only be as detailed and specific as the question is detailed and specific. Good questions also include a sketch or a photo that illustrates your issue. (:< D)