Motor was running normal and then started making a different and slightly louder sound. Actually sounded like my 20HP kicker motor. Actually what I really like about this motor is how quiet it runs. Stopped the boat and shut the motor off and raised the motor to check the prop. Everything seemed fine. Started the motor up and pushed the control forward to start going and when it got to around 1500 rpm, rpm's wouldn't go any higher with the throttle pushed farther forward. Stopped and started few additional times with the same result. None of the "Indicator" lights came on while running. All were working. Any idea what could be the issue? Any comments greatly appreciated.