Hyundai E320D 32 in. LCD Television , No signal fault
I had exactly the same problem with mine this week. After taking the back off and poking about with my multimeter (I am an electronics engineer!) I discovered that the power supply board is screwed to the chassis with 4 screws (three of which are system grounds(earth)).
All three of the earthing point screws had worked their way loose - The fourth (top left as you look from the back) was still tight, but this one does not ground the board. After tightening these back up the television is now working fine again. - so fingers crossed! I will report back to this thread if it stops again! Please post here if you have the same fault and it does or doesn't fix it.