Panasonic Plasma TV Hum/Whine?

[mtflynner]

Have a 15 month old Panasonic 50" TH-50PX75U and have noticed a high-pitched hum/whine that seems to be triggered by whatever's shown on the display. Does not seem to be tied to the audio, as the hum/whine happens when muted; the hum/whine also occurs regardless of source (cable, DVD, etc.). On DVDs or shows where the movie cuts back and forth between two scenes, the TV will repeatedly hum/whine on the one scene but not the other.

Anyone seen/experienced this type of issue before? What causes it? Any way to address/fix? What's Panasonic like to deal with if warranty is expired?

[snappy_snoopy]

In my experience high pitched hum and whine as you put it comes from switch mode power supplies where the inductor windings have come loose and vibrate in the audio frequency range. When i built a switch mode power supply for a university project i noticed this hum when i did not wind the inductor windings tight enough. This is also a common problem in laptop and other small power supplies.

It could be that for some reason on scene changes your tv requires a sudden burst of power, and this triggers the inductor to vibrate !! Then again without knowing exactly how the power supply is build and what type of switch mode converter is being used i can also not comment on whether this is the case. Just some speculation on my part.

Hope that helps :o Dont know about the panasonic service department either much help i am :rolleyes:

[bandphan]

Have a 15 month old Panasonic 50" TH-50PX75U What's Panasonic like to deal with if warranty is expired?

Has the set always done this? Panasonic's cs is priddy good, and as with most manufactures will provide some limited tech support via the phone. Have you searched through the owners thread at avs forum?

[walter duque]

Have a 15 month old Panasonic 50" TH-50PX75U and have noticed a high-pitched hum/whine that seems to be triggered by whatever's shown on the display. Does not seem to be tied to the audio, as the hum/whine happens when muted; the hum/whine also occurs regardless of source (cable, DVD, etc.). On DVDs or shows where the movie cuts back and forth between two scenes, the TV will repeatedly hum/whine on the one scene but not the other.

Anyone seen/experienced this type of issue before? What causes it? Any way to address/fix? What's Panasonic like to deal with if warranty is expired?




Unplug tv and cable box from outlet for at least 1 hour, this will discharge the powersupply. I have a similar problem with my pioneer have to do this about every 6 months.

[walter duque]

Have a 15 month old Panasonic 50" TH-50PX75U and have noticed a high-pitched hum/whine that seems to be triggered by whatever's shown on the display. Does not seem to be tied to the audio, as the hum/whine happens when muted; the hum/whine also occurs regardless of source (cable, DVD, etc.). On DVDs or shows where the movie cuts back and forth between two scenes, the TV will repeatedly hum/whine on the one scene but not the other.

Anyone seen/experienced this type of issue before? What causes it? Any way to address/fix? What's Panasonic like to deal with if warranty is expired?
Also check if you added a new appliance to the same circuit. Also plug tv into a different outlet. could be your outlet to who knows. Sometimes people panic but it could be an easy solution. Good luck...

[sneakystiffler]

I have the same issue with the same model TV. Mine was still under warranty and the power board was replaced along with another board and it still makes this noise only on certain scenes. It seems to only happen on scenes with a lot of white or lighter color in them? The company working on my TV under warranty took my TV to their shop last wed and still can get it to reproduce the noise.

[PHANofPHUNK]

may be ground loop