According to the customer, all 30 receivers have the high pitched whine on the lower channels; all the upper channels appear to be working fine. My thought is that since it is affecting all receivers that the issue is somewhere upstream of the rack and my gut is pointing to the ground like you stated, water penetration or the LNB. By the way, this is a SMATV not a Head End. I'll know more tomorrow, thanks for the assist THV and Goodsky. Much appreciated!
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