Topband: Pixel Loop feed point failure

[Frank VO1HP]

The Pixel Loop (now DXE PRO LOOP) has an out door preamp that is fed power
over the coax.  the voltage  is 20VDC fed over the RG6 which is mated to a
standard chassis type F jack.  In my installation near the ocean my loop
has failed twice at this junction point.  The centre conductor and the F
jack are essentially burned black or brown.  Just took it out of service
today fo second time with same fault.

I am using my standard water proofing methods of tape and a generous cocoon
of duc seal water proof putty.  the power is fed to the bottom of the
preamp box so it is somewhat protected but still failing.    the drain
holes are not obstructed.  Has anyone else encountered this failure  with
the Pixel Loop?

73
Frank VO1HP