the easiest one would be to lower the gain, not by a big difference, and note the changes.
then adjust as required to be closer or under the red line. anything above the red line
appears to be an ‘overload’.
check this thread https://discussions.flightaware.com/t/read-set-gain-from-skyview-and-gmap/37140
for an easy way to set/check gain.
evangel