Thank you all for your reply's. The boat is powered with a 12 amp hour lead acid battery & is fully charged, The receiver is powered with a Action BEC 6 V. The motor is a 300 Watt 13 pole motor driving a 1.5 meter boat through a 80 mm 4 blade propeller . The motor will run perfectly when I disconnect the sound unit & connect directly from the receiver to the ESC,also motor motor will run when I have the sound generator connected in the line from the receiver to the ESC but will stop when I put a few revs on the motor, some times it will run up to full revs for a few seconds & then cut out, sometimes it doesn't start the motor at all.The sound generator runs well all the time & revs up & down without any problem. It is only a problem when the sound generator is connected in the line from the receiver to the ESC to motor.
.12 volt Battery to--- 6V BEC to--- receiver--- to diesel sound unit--- to ESC--- to motor