I have the system connect to a Sony Blu-Ray, and a Comcast HD-DVR all with HDMI. The Blu-Ray plays with no problem, but when I try to watch tv the picture goes on and off and I get no sound.

This is a Comcast baby - U are paying them plenty for the service - they should help you with the remote. Don't let them off the hook.

If your Sony Blu-Ray player and LG TV are recent models, each should have an HDMI cable connection. HDMI is an method to connect your digital video and audio devices with just a single combined cable. In the case of your LG TV, using an HDMI cable will allow you to send the HD video signal to your TV's screen, and allow you to hear the sound through the TV's speakers.
Your LG TV may have multiple HDMI connectors, to allow other devices to send signals to your TV, such as a cable box or satellite box or digital video recorder (DVR). Your Sony Blu-Ray player will usually have just a single HDMI connector.
Purchase an HDMI cable from your local electronics store. There are different versions of the HDMI specification, and you should get a cable that you can verify is certified for the HDMI version 1.4 specification.
Plug one end of the HDMI cable into the Blu-Ray player, and the other end into one of the HDMI connectors on the TV, noting which one you selected.
When you turn on your Sony Blu-Ray and your LG TV, you should use the remote for the LG TV to select the input source. Your LG remote should allow you to select the HDMI input connector you used, at which point you should see the display of a DVD playing on the Blu-Ray player. If you cannot hear the sound, use the LG remote to increase the TV volume.

there are conversion boxes as well as conversion cords check out radio shack

have you tried to connect the Philips direct to the TV's hdmi?

Could be the resolution on the bluray is set to 1080p which may be out of range for the receiver or even the TV for that matter. If you can reset the output resolution of the bluray to 480p first, just to establish a picture then try 720P which all HD tv's and receivers can handle.

I did a quick search and could not find the resolution reset procedure for this unit. Other units will reset if you press and hold 2 or more buttons together.

One hook-up per sentence please - try again!

Try this:

Purchase a 3.5 mm jack (it will have a smaller connnector going into the TV and Red and White connectors on the other end).

Pull all the other cables running into the Blu Ray player out so that you are only left with the HDMI Cable coming from HDMI Out (DVD) to HDMI/DVI In (TV), along with the 3.5 jack.

You will be able to play the TV sound through the system.

Try this set up-

Use an RCA audio/video cable for this set up (Yellow/Red/White).

Connect from the Video out (Yellow) connection on the back of the cable box to the Video in on the back of the DVR.

Connect the audio (Red/White) cables from audio out connection on the back of the cable box to the "Audio in" on the back of the DVR.

This should still get you a decent picture but not a true HD picture for your recordings.

When you set the timer to record set it to record either E1 or E2 depending on which input you connected the cable box to and ensure that the cable box is tuned to the channel you wish to record.

*** NOTE: If you keep the HDMI cable connected as you have for the cable box and watch normal TV through the HDMI input on the TV you will get HD programming for your general viewing but still have the option to record with the DVR at a lower quality. ***

Good Luck and please rate this solution....

1. Connect cable to cable HD DVR box, connect video out of cable box to Sony receiver TV video in, connect audio L and R out of cable box to Sony receiver TV audio in and connect TV out of receiver to video in of Panasonic projector 2. Connect Audio and Video out of DVD player respectively to DVD in of receiver. Good Luck :)

I have the same problem with comcast HD, completly useless talking to them, they do nothing to assist

hey, im hopeing the tech will be able to sort it out for you, theres not much any of us can tell you what he couldnt tell you tomorrow so be patient.

if he doesnt get it sorted drop us a comment and il try to help you.