I have spigots on both my fermenters. The trub never gets up to the level of the spigot. But I also pour the chilled wort & top off water through a fine mesh strainer to get a lot of trub out.
I had exactly this problem, first I tried with lower fermentation temperatures(from 68 to 65), it didn't work, then I changed the sanitation, the problem persisted... I tried MANY MANY things, none of them worked.
I found the solution after searching a lot on the web, do a rolling boil of an hour or more, after that I never had the problem again.
bottling from a primary, this is your problem.
Barnzy02 said:+1.
Rack off of yeast cake, then bottle.