Engine 'ticking' Noise

#1
Yamaha 2007 F115 (4Stroke) - 190 hours - Very well maintained with regards to maintenance schedule - still under warranty. Last two fishing trips I've noticed a 'ticking' noise. This ticking noise gets more rapid with higher RPMs and slower with lower RPMs. Took Cowling off at the boat dock and pressed in the free accelerator button to take out of gear in order to rev engine a bit and you can clearly hear the 'ticking' noise. Thought maybe it could be noise coming up from lower unit, that is why I took it out of gear in order to rev up engine a bit. The engine runs like a 'top' without any issues or bogging down, great fuel mileage, etc., etc.

Could it be the valves need adjusting, stuck lifter? Posted this on another board and someone said fuel pump could be the culprit.