[haarvi]

Update:
Our tv hum is still showing its ugly noise.
(Actually, the hum is not confined to the tv. It also appears on one of my two headphone
amps - the electrostatic amp - unless I detach the cable wire from the cable box.)
The hum , persistent as it has been, did a disappearing act this afternoon when the third set
of cable techs came.
The first cable guy to address the problem - an installer - swapped our cable box.
And when that did not disappear the hum, he told me that the eccentric cable connections
to the tv - as per the unusual design of the Loewe tv were the likely culprit.
The second cable guy who came, added a ground connection to the cable line.
(Possibly a second ground.)
Which seemed to resolve the hum.
Until it came back.
The third guys - one a supervisor - said that HDTVs not infrequently add all sorts of i
ndeterminate gremilins / compliations to the electrical system.
Which are beyond the purview of the cable company to deal with.
He suggested we might start by upgrading our surge suppressor.
(Or by adding a power conditioner - which udea he gave assent to when I suggested this
as an alternative to a surge suppressor.)
The second of the two techs suggested I have my house wiring checked to see if the
house ground was operational.
He said that they could have checked the house ground - with a ground wire - to see if
grounding took away the hum.
But only if the hum was present.
Which it wasn't during their visit.
Unfortunately, the hum came back later this evening.
Any further thoughts / suggestions?