997si question

The right side of my screen seems to be blurry or out of focus compared to the left, which is practically like watching a black and white television show of the bottom. The transducer is not blocked, makes no difference with or without the trolling motor or big motor. I have gone back and forth from 800 to 455khz and no difference there. The 455 gives a brighter and clearer picture overall. I have not downloaded the latest update, but plan to today. I have downloaded an earlier update. Could that be the problem? Did it not install properly?? Any help would be appreciated. I love the unit and what I can see under the surface, just want to resolve this issue before the weather breaks.