522c slow after upgrade

I updated my 522c this week to version 2.5 and i have an issue with the map and waypoint update on the screen. i'm trolling less than 1 MPH and the screen is not updating fast enough. There is like half the map (contour lines and way points). It is also taking a long time to update between zooms (two minutes). The speed update is working good and im finding all my old waypoints once they show up on the screen.

Never had a problem before the upgrade to 2.5. Not sure if i have something set wrong or not. Any advise would be helpful
Thanks,

BB