Hmmm... I've never seen such a thing... Are you sure of what you have?
You want the FM trap to be "In" or on. You have several close by FM stations that might interfere with channel 8. You might even need additional external FM filtering in front of the pre-amp.
Signals at night time often are better than daytime due to the reduced background noise levels. As soon as the sun comes up, you usually loose those stations.