Failsafe MUST be configured once with the desired channel values (hold or no pulses are not supported) while the RX is up (wait 10+ sec for the RX to learn the config) and then failsafe MUST be set to RX/Receiver otherwise the servos will jitter.
Telemetry: the 2 RXs I have are sending different information in different format
RX-5: RX_RSSI=RSSI=sort of RSSI or link quality, RX_LQI=number of connection lost, TX_RSSI=RSSI from the TX perspective, TX_LQI=percentage of received telemetry packets
RX-9-DR: A1=RX Batt (Ratio=12.7), RX_RSSI=TX_LQI=percentage of received telemetry packets from the TX perspective not RX, TX_RSSI=RSSI from the TX perspective, TX_LQI=percentage of received telemetry packets