Checklist plugin stops updating, (strange problem)

I were about to fix the db levels..

```
'''beforeEngineList - Radio Links > 6db margin TODO: figure out how to read db levels'''
if type in ['RADIO', 'RADIO_STATUS']:
if msg.rssi < msg.noise+6 or msg.remrssi < msg.remnoise+6:
self.checklist.set_check("Radio links > 6db margin", 1)
else:
self.checklist.set_check("Radio Links > 6db margin", 0)
```

notice the "reversed" checkboxes, (makes the problem easier to discover), when signal/noise level drops, and the checkbox is set , it will never recover, - for some reason..

I would expect the widget to updata and change the checklist anytime - seeing no logic that could prevent it.

Start by tracing the shown RADIO and RADIO_STATUS branch and its checklist.set_check calls. Reproduce the transition where signal/noise drops below the 6db margin and then recovers, observing the checklist widget. Done means the checkbox updates correctly in both directions as the radio levels change.

Written by the indexing model from the issue text.