Tell us more about your system- regular or SWM LNB, how many receivers/DVR's, how they are wired, multiswitch or not, and is the problem the same on all receivers?
If you have a non-SWM LNB (4 coax coming from it) and those 4 coax go to a multiswitch, then one of the 4 coax or associated connectors is most likely your problem (13V, 22KHz input on the multiswitch).
If you have a non-SWM LNB (4 coax coming from it) and those 4 coax go to a multiswitch, then one of the 4 coax or associated connectors is most likely your problem (13V, 22KHz input on the multiswitch).