I recently built a POE mmWave setup (Ethernet-> POE splitter -> ESP32-ETH01 + LD2412). It works very well in the open air. However, my plan is to put it inside my ceiling (ie, above the ceiling drywall). As part of that, I put the ESP+LD2412 portion into a single gang box and taped the LD2412 to a blank faceplate. This didn’t work, as it reported constant motion and constant presence. The plate is a standard plastic Leviton plate, which I thought should work. What am I missing? I tried recalibrating, but without luck. Any other ideas?

Again, my plan is to put the whole box (faceplate side down) above the ceiling, without cutting the drywall, so the sensor would be going through both the faceplate and the drywall.