# Solved: loud hum with new lcd tv



## wtxcowboy (May 25, 2004)

thought i'd get creative & plugged an rca cable into the red/white jacks on back of new lcd tv & connected them to the power box/subwoofer of my computer's logitech speaker system, but have a loud hum! can hear audio fine otherwise. is there a solution to getting the hum out??? Thx


----------



## etaf (Oct 2, 2003)

possibly an earthing loop 
is the TV earthed
is the Powerbox earthed


----------



## wtxcowboy (May 25, 2004)

tv & speaker powerbox are both grounded or at least plugged into a grounded 3 prong outlet etc. figured it must be interference from the wiring in the wall or other componenents perhaps, who knows. thx for the input!!


----------



## etaf (Oct 2, 2003)

that may be the loop - if all grounded 
or as you say interference - 
what type of cable is it - have you used double shielded


----------



## wtxcowboy (May 25, 2004)

just using a regular rca cable with red/white jacks. could it be the output of the tv is too much for the logitech g51?


----------



## etaf (Oct 2, 2003)

i would not think the output is to high as it would distort - is it a low frequency hum - can you connect it up with out the cables near any others - eliminate pickup/interference


----------



## JohnWill (Oct 19, 2002)

Try pulling the cables out one at a time until the hum ceases.


----------



## wtxcowboy (May 25, 2004)

had to unplug all the audio cables from the computer & so no hum. even with the pc turned off would hum, so guess it's either or. oh well lol.


----------



## JohnWill (Oct 19, 2002)

This is a grounding issue. You need to investigate if there is a sneak path to the power in one of the devices. Have you reversed the power plugs and/or connected them to the same outlet?


----------



## wtxcowboy (May 25, 2004)

i did change outlets for the tv & the powerbox, didn't matter. tv is ~20' away from the computer so using a 25' rca cable & different wall, different plug altogether. it's no biggie, i'll just detach the pc audio 4 color cable if i need surround sound for my tv or buy another set, they're cheap enuff now.


----------



## JohnWill (Oct 19, 2002)

Well, that's one solution. What happens if the new set has the same issue?


----------

