"clacking sound..."

[callmwater]

2 year old Suzuki 200. Just had 200 hr service - immediately began "clacking/ticking" sound (kinda like playing cards on bicycle spokes!), mostly at 4,000rpm but perceptable at lower rpm. Not noticable at idle. Appears to be in engine, not lower unit. Tried adding noise reducing oil additive. No change. No warning lights. Rep says probably timing chain. No harm.......???
IDEAS?

[boats.net]

May still have warranty and need to take it to dealer to get it repaired or a record of problem in case something does happen in future.