New CRT installed

[Charlie]

Got my rebuilt CRT installed today and have a really nice picture. A big difference from the original! This photo really doesn't do it justice.

I am having a weird focus problem under certain circumstances. This problem has been coming on for a while. A few weeks back, I noticed it losing it's focus for a moment and then it would come back. Would do it just every now and then. After putting in the new FBP, it lost focus a couple of times so I changed the 1V2. Didn't help any. Then, I noticed it would lose focus with certain pictures on the screen. One example is pictured below... it was the on-screen VCR menu. Another example is at the beginning of a movie when they show that is either a PG or R rating. When I would turn the color down, the picture would come back into focus. Turn the color back up and the focus craps out and also losing some of the side. Noticed the heater brightness in the 1V2 would go down with the color turned up on these pictures. Then I changed the HV rectifier and this corrected most of the problem. Now, it only loses focus during those same screen shots if the color is cranked up a lot.

Viewing programming pictures, the focus is good and sharp. Any ideas on why the menu below would cause it to crap out?