Hissing sound coming from tv speakers even when sound is off

I own the Vizio SV420M 42 inch television. I have had it for about 4 years. It has been a great tv. About a month ago, when I turn on the tv, on random occasions I will hear a static / hissing noise coming from the tv speakers. I turned the volume down on the tv all the way to 0, and the static / hissing is still heard. It is loud. It only stops if I turn the tv off and on again. The static sound will then go away, until I turn the tv off for a while and turn it back on. I have checked all cables, took them out put them back in and nothing helps. I have the Sony HT260H sound bar hooked up to it using an optical cable. I also have a PS4, direct tv receiver, and x box 360 hooked up using HDMI cables. I have been searching online for a month now, with no help. I have contacted Vizio support, and all they could tell me is it's no longer under warranty and they give me numbers to tv shops. I don't want to take it to a shop if it's an easy fix. Please help!!! Here are some more observations I have made. The hissing sound happens no matter if the tv speakers are turned on or off. The hissing sound is coming through the tv speakers not the sound bar. When I pan the balance back to right and left speakers, the hissing sound doesn't change. When I turn the volume up on the tv to about 45 the hissing starts to pop and it stops.

Discussion is locked
Reply to: Hissing sound coming from tv speakers even when sound is off
PLEASE NOTE: Do not post advertisements, offensive materials, profanity, or personal attacks. Please remember to be considerate of other members. If you are new to the CNET Forums, please read our CNET Forums FAQ. All submitted content is subject to our Terms of Use.
Reporting: Hissing sound coming from tv speakers even when sound is off
This post has been flagged and will be reviewed by our staff. Thank you for helping us maintain CNET's great community.
Sorry, there was a problem flagging this post. Please try again now or at a later time.
If you believe this post is offensive or violates the CNET Forums' Usage policies, you can report it below (this will not automatically remove the post). Once reported, our moderators will be notified and the post will be reviewed.
- Collapse -
Since the soundbar works, why not unplug the internal?
- Collapse -

I would unplug the internal and not worry, but if its another problem with interference with the sound bar or ps4 or something else, I would like to know. If it's just the tv going bad, then I'll unplug and only use soundbar, but if its something else I would like to know before.

- Collapse -
And that you can test.

Unplug the soundbar and PS4 and if the hiss goes then you have your answer to that question.

It sounds like you want the TV repaired. That's going to cost but given the story I would have taken the zero cost fix.

- Collapse -

I have tried to unplug the sound bar's optical cable and the hissing continued. I unplugged the PS4's HDMI cable ( actually all cables except power cable) and hissing continued. I won't get the tv repaired, I will probably get a new one during black Friday if the problem persists. I just want to know if its the tv or another causing factor so I can get a new tv and not worry about interference with the new one. The only thing that stops the hissing / static sound is to A. turn the tv off and on again, or B. turn the volume on the tv to mid or high level then the hissing stops and sound goes back to normal. I just really want piece of mind that it is for a fact the tv messing up and not my soundbar or other device causing it. (i.e someone with the same problem and found the solution). Truthfully at the moment its just annoying having to turn the tv off and on again every single time I want to watch it, but again its just an annoyance. Thank you for the video on how to unplug the speakers.

- Collapse -
I understand the worry.

For me it sounds like an audio amplifier failure in the TV. Seems a shame to replace it when unplugging something simple would let it continue in service.

Glad the video helped you see how simple it might be. Remember you only need to unplug one of the two wires to the speaker. I take an extra precaution and wrap the loose end with a single wrap of electrical tape. In a pinch I've seen folk use masking tape.

- Collapse -

Ya, I just want to know if it's the tv or something else, before I address replacing the tv or cutting the wires. I watched the video last night, seemed like a very easy solution, if it is the TV's problem. Thanks again

- Collapse -
Late Comment

If you have headphone out on the TV (some do), plug in an old pair of earbuds.

CNET Forums