Ft60 lack of top end revs

[Tinnyman]

Hello
I have a 2009 ft60 . Now has 150 hours on the motor. I have noticed its losing top end revs, and outright power. When near new it would rev out at 5800 rpm with ease. Now it's battling to get to 5200 rpm, and feels sluggish in a bit of swell. At idle and at revs it's still very smooth, but lacks power. Nothing on the boat has changed.
Any ideas? The dealer I bought it off offered no help, next service I'm changing dealers.

[boats.net]

If this is a carb model may need to clean carbs, if fuel injected then need to have fuel pressure tested and test fuel injectors.