Hi everybody,Today i went out on the boat with my new unit for the first time.I have a few problems to work out.First once i hit 20mph or more i loose depth readings,I figured this would probably happen.I'm gonna try and lower the TD and hopefully this will fix the problem.Second i have a crazy roostertail that just completely soaks my outboard.I'm hoping that when i lower the TD this will help get rid of the roostertail,But if it doesn't whats with this rubber plug i keep reading about?Does humminbird have one for the 998 TD?If they dont offer the plug for the 998 what else can i do to fix the rooster tail problem?Finaly today was a bright sunny day and i couldn't see the Si picture at all,My wife had to hold a hat over the unit to block the sun just so i could try and see it.Does humminbird make a shade cover to help with this problem?The regular sonar picture at slow speed was just awsome i love this unit and gotta work out these bugs so i can really enjoy this system.Any advise would be greatly appreciated....Thank You Jim.....