Right now, I have an RFD900 in a cube orange plus serial port 1, and DBR4 in serial port 2. I have tried all the online solutions, but they don’t seem to work. The program is telling me to power on the transmitter, even though there are lights on the DBR4, as well as being connected to the GX12.
Keep those radios and their antennas separated as much as possible.
We would need more details, like all your parameters and your ELRS settings to help more.