Don't sit with your back to a wall - i.e. head within two feet - it will collapse the soundstage and completely mess up the bass. It is like listening in a cave or tunnel - sur eit may sound vague and wide but imagine using the left over cardboard roll from two paper towels and placing one to each ear...when you listen along a wall you are partially doing this Ceiling/wall/floor is like three sides of a tube.
If you can't fix this then get some rpg skyline diffusers behind your head.
If you can't fix this then get some rpg skyline diffusers behind your head.