When I power on all my instruments (D100 D120 Garmin296), I noticed that my EFIS was not sending OAT to the D120, which in turn prevents the %power calculation. Upon checking my network, the devices can all 'see' each other and I rechecked the configuration - but the devices are shown as "offline" in the network status, and the values provided list - normal e.g *OAT are shown as *?OAT instead. What does this mean, and how can I get them talking again?