The LG 42px4dv-aa States that HD service is not available surely this tv has HD

Try manualslib.com

http://www.lg.com/uk/support/product/support-product-profile.jsp?customerModelCode=42PX4DV&initialTab=warranty&targetPage=support-product-profile that is the website for the owners manual if it wont let you click the link then just go to lg.com and search for your model and it is downloadable good luck

Here you go fella, i had the same problem! Enjoy:

LG 42PX4DV Sky Code is: 0206

what do you mean? it doesnt set to high definition display?
maybe its already on but the source of the video / scene is not that clear as what you want.

LG 42PX4DV-AA
will not find channels digital 7, 9, 10

Have you made sure the box is set to send a HDTV signal to your LG? Example 720p, 1080i, or 1080p? You usually have to set the resolution in the v+.

Do you use a regular antenna, or cable/satelits tuner?

I use only satelite tuner, and had the same problem on a differnt TV. I solved it by connecting a regular antenna (actually just a piece of cable) and go through the search and store routine once. Then the TV remembered that it was configured. Before that it thought it was "fresh out of the box" every time.

I found the fix. Had the same problem.
I right clicked on the sound speaker icon in the bottom right of Windows 7.
Chose Playback Devices.
Once this window opens, then make sure you are on the Playback tab.
Scroll down until you see the HDMI Device. (Mine was hidden at the bottom of the list.)
Then choose "set as default".
The sound will begin playing on the TV with only the HDMI connected......no need for an extra audio cable.

I had the same problem with mine, LG techs came out to my place and upgraded the software and the problem went away. I had mine for nearly a year when it started, supposedly is it quite common. Anyway, dont worry too much about it as easily fixed. I have been very happy with my TV and have used it everyday for 16 months. Just want a higher resolution TV now.

Sorry to tell ya that the high pitch tone is a very common complaint ,mostly from our lady friends.. As their hearing range is alot more sensitive then their male counterparts. The "singing Coil" problem is nothing more then a loosely wound coil or deflection yolk and even sometimes even the HI voltage transformer. There are a few tricks to try to MINIMIZE only!! The singing of the coils. Such as siliconing the coils . Sticking wood pieces in between the coils or tranformer bases. But the really only way to eleminate this problem 100% is to replace the parts thats singing. And this is not a job for the handi-person.. Theres always a hi voltage issue thats present even when a tvs unplugged!!! Please seek a quailified service tech to assist you inj this nissue. GOOD LUCK