This may be known, but I report it.
I have installed ROVER 4.2.3 and configured the relay.
I set following parameters.
SERVO９_FUNCTION: GPIO(-1)
RELAYIPIN: AUXOUT1
RC8_OPTION: Relay On/Off(28)
The relay did not work with these setting.
Then I tried other settings.
SERVO10_FUNCTION: GPIO(-1)
RELAY_PIN2: AUXOUT2
RC9_OPTION: Relay2 On/Off(34)
In this case it worked.
I tried other relay channels as well and they worked fine.
However, only the first relay did not work.
I have tried everything, but it didn’t work.
Finally, I used RC7 instead of RC8.
RC7_OPTION: Relay On/Off(28)
When I did that, it worked fine.
The relay worked except in RC8.
The reason it did not work well with RC8 seems to be that RC8 was set to MODE_CH.
I mainly use COPTER, so I thought RC8 was free.
I also didn’t realise that the MODE_CH and RC8_OPTION options were incompatible.