NO, NO, NO, nothing tell you that the head end level has not got down 5 dB. When you are talking 48 db are talking GAIN or Level output. 48 dB seem to be high for gain GAIN and if you talking output level, you should have mentionned 48 dBmV.
Joe 50
This is CABL.com posting #306061. Tiny Link: cabl.co/mbrMD