Hum Loop on Computer.?

Question

I'm using a Digital Set Top Box for cable TV reception given by the CableTV provider(Asianet). The cable is directly connected to the Set Top Box and it has three outputs. 1 Video (RCA) 2 Audio L,R(RCA). I have connected the Video output to the RCA input of my TV Tuner Card. The Audio cable is connected to the Stereo IN (Line IN) of my sound card.

My problem is a Hum Loop is being created through the Computer's Earth point. I assume this is happening because the output from the Set Top Box is connected to two different devices, (i.e Sound Card & TV Tuner Card).

If I cut off the Earth wire of the computer, the loop disappears and I can view Cable TV fine.

My question is, "Is there any way I can get rid of this"?

I know using computer without the Earth point is a bad idea. Could anyone please tell me the problems that can happen when we use a computer without an Earth Point?

If any particular Computer Components affected, please let me know.

Answer 1

If you remove the earth on the computer, you also defeat any surge protector you may have it plugged into.  It is also there to provide a safety connection to earth in case there is an electrical malfunction

  Another way to possible get around this is to connect a piece of wire to the metal chassis on the set top box to the chassis on the computer.  That might fix the hum and then you can restore the earth connection on the computer.