It's probably just the hops then. Pellet hops disintegrate and form a fine sludge, which should sink, hopefully. If not, give it a very gentle stir on the surface to encourage them to sink. Use a sterilised spoon obviously. You may need to siphon the beer off through some kind of cloth when you bottle it, if there is still hop residue in the beer. Fasten a piece of sterilised muslin or similar over the end of the siphon that goes into the beer. Or a piece from a woman's stocking, But if you are that close to a woman who wears stockings, you are probably not a home brewer. :)
I've never had to do this though, if you are patient, and if you can put the FV in a fridge or somewhere cold, the hops should sink to the bottom.