I am putting on an APC 16x8 prop on an Eflite Albatros. Motor is a Dymond 2832 (similar to eflite power 32) and speed control is Dymond 60a with 5a BEC. Battery is zippy 14.8v 3000mah. Vibration noise only commence when i am at slightly below half throttle. whan i am past half throttle vibration noise disappears. i have already balanced the prop but have not yet balance the spinner or the backplate. i thought that if something is out of balance it would shake and vibrate throughout the range of rpm and NOT at just slightly below half throttle and vibration disappears at any other range. any help on this matter would be much appreciated.