This unit has previously been showing a distorted picture Then it began to make a hiss everytime you powered it on however after making this hiss it failed to turn on. This problem has been getting worse, and is now to the point where the unit will not turn on at all. It has stoped making the hissing noise, and now has high pitched noise coming from it, when you power it on for about 3 seconds, then the unit turns off. Does anyone have any ideas?