My shutter isn't connecting to the rotator - I think it might be the Xbee. What one/where should I buy one? About 1 out of 20 times I boot the shutter isn't connected. Are both rotator and shutter Xbee's the same? or is one a TX and one a RX? I don't want to order the wrong thing. Must a new one be synced to the one in the rotator?