Tilt affecting engine RPM

[florida_1959]

Has anyone run across a problem where you attempt to trim the engines under throtle and you have one engine lose RPM? I was running along each engine at 4500 RPM when I wanted to trim the engines to play with the attitude of the boat. I pressed the switch for both engine trim and my starboard engine (only) immediately dropped to 3500 rpm without a movement of the position of the handles. I trimmed back down but no change. Had to stop and turn off the starboard engine and restart, went back to full RPM as if nothing wrong. This only affected the starboard engine, port engine never changed and was never shut off. Could the trim relay be somehow hosing up the electric circuit, causing somehow to go into reduced rpm? This does not happen at low rpm as I trim up while underway to avoid the sand bars while idling around. Engines are Yamaha 2001 200HPDI's

thanks

[boats.net]

Check all wire connections at battery and on engine, may have a loose ground wire.