Originally Posted by wfield0455

Since all the Cortex does is provide servo outputs, the same as a receiver, if you connect an SBE-1 and sbus servos are jumping, that really can only be caused by the SBE-1 as it's driving the servo. Not saying the SBE-1 is broken but it appears it can't handle the frame rate provided by the Cortex. Did you configure the Cortex to use analog servos or digital servos? I'm guessing digital by the symptoms you're describing. If so, most likely that's the problem. It doesn't matter if the actual servos used are digital or not, what's important in this case is whether or not the SBE-1 can handle the higher frame rate and my guess is it can't. If the Cortex is configured for digital servos, change it to analog and try again.