You can also hit the box diagnostic page by going to the internal IP. Usually on some brands it is 192.168.1.100 (note not the same IP as the one you log in with to settings)

If you go in there and post your signal levels. Power DB down stream and up stream as well as SNR I can tell you if you're out of spec.

Most likely the signal is low and all the splitters in the RV aren't helping much. You can try to connect it to the satellite input which is a straight shot to your TV and see if that helps by removing all the other splitters. You can also try to connect it directly outside to the wire there and see if it will sync up.