my manhattan RC-1978 has worked well for the last few years. However for the last month or so some channels are becoming weaker or lost altogether . the stations still show on lyngsat as being active . did a reset and a rescan that made things worse . some channels that were weak before rescan disappeared entirely after scan . Is it possible the LNB is going bad? It's one of those C/KU combos from china that mount in the center of the dish. Is there any way to test other than buying a new unit . Would a seperate Cband and a off set KU lnb be a better arrangement. I have a10 foot mesh dish . it has been checked for warp . Don't know where to go from here.