Certainly not unheard of! Last year I was doing some reconfiguring of our RV sat setup while at our upstate NY vacation cottage. To avoid interfering with the Hopper in the cottage that's connected to the permanent 1K4 there, I set up our portable 1K4 to use with the RV setup instead of connecting the RV to the permanent Duo Node as I normally would. During my testing of the new wiring layout, I compared signal levels between the two Hoppers (both on EA), and was surprised to see the cottage Hopper levels were about 10 points down from the RV Hopper levels. I stuck my meter on the permanent dish, and made sure it was tweaked up as high as I could get it, but even right at the two dishes the numbers were off. As a quick test, I swapped the LNB's between the two dishes, and looky there! The signal levels swapped as well. I took the lower reading LNB off and shined a bright light beam into the translucent cover, revealing noticeable moisture on the inner surface. Installing a spare EA LNB brought the signal levels back to nearly identical on both Hoppers. I couldn't find an obvious crack anywhere, but since I had a few extra EA LNB's anyway, I just tossed it in the trash.