Thanks, Krysta. Since these are $18 each plus shipping, can I try unplugging the servos that have the long extensions and checking the remaining servos? We're talking about $90 plus shipping, and it may not be the remedy. Am I just being a cheapskate? Also, is the filter/extension linked above heavy duty? Is there a rule of thumb regarding heavy duty leads needed when exceeding a certain length? Thanks again!

Oh, I forgot to mention that the PT-19's elevator and rudder were jittering without the wing being plugged in. The wing has the only extensions. The rudder and elevator servos are mounted beneath the cockpit. The Mayhem has an extension on the elevator, as well as the aileron servos.