Toshiba 50HDX82-Noise while off,color probs

I have a Toshiba 50HDX82 that is making a high pitch noise while turned off. I called the service place and they said it is a well known problem with the high voltage transformer and that they would fix it at my house.

Also,one time when I turned the set on,the picture ws in a negative looking color format-like a film negative. I turned it off and back on,it flickered in and out of this negative format,turned it off and on again and it hasn't done it since.

Since i have the service people coming out,is there a documented problem with the color or was this just a one time fluke that probably won't happen again?