I've got an older Sony KP53HS10 RPTV. It's been a great HD performer except for what I would describe as a slight "flagging" of the 1080i picture in the bottom left and top right corners of the picture. It also appears that the RGB CRTs don't converge properly in these areas. I'm familiar with the service menu and have done convergence adjustments to it in the past. I just can't get the guns to line up on the far edges of the picture. Is this just the nature of the beast or are there other adjustments that can be made to rectify the situation? Thanks in advance for any and all replies.

MM