I have a hitachi tv model 42edt41 year 2004,2005

I have the same tv and had the same problem. I found a posting that stated to re-solder a connection on the cable for the "y" boards. I used this and my tv is perfect now. The part that needs to be re-soldered is the ribbon cables at the bottom of the tv that go from the boards straight to the screen. On the inside of this ribbon cables there are 4 small components that have "100" on them. On each end of each of these pieces, re-solder them. Since I had my tv completely apart I re-soldered all of them across the bottom. No problems now!

Sounds like it is time for a new tv