This may sound like a dumb question, but are you by any chance activating the horizon switch and then the rescue without returning the horizon mix back to off?
If so, that would explain why the value stays at zero.
If I do that with my mixes, turn on Horizon, and then Rescue, the 2 mixes would subtract the values from each other and the net result would be close to zero.
I know the following does not apply to your JR, but as a reference, I only use one mix for Rescue with a value of -99 on my Futaba and it worked like a charm every time in 5 years of flying.
The only reason for using two mixes to get -200 is simply to offset using the Rescue after using Horizon.
I have used Horizon 3 times in 5 years, I just dont see any use for it. I only used rescue for maybe 50 times mostly for doing demos 99% of the time.
Dont give up, we'll figure this out.
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bavarianDEMON- Team Kontronik - Scorpion Motors-