I have a 4-5 year old RP Panny. It has been gradually getting a little dimmer, to the point where I'm now in full torch mode just to be able to watch normally. Are the crt tubes dying, all together, or would you think it is some other issue? Obviously, spending a lot of money to diagnose/fix the problem doesn't make sense at this point.

Thanks

Have you consulted the relevant threads? If not, use search to find them.