The hyper module is responsible for scan conversion in many Toshiba sets. Some of the CRT RPTVs have had issues with bad capacitors in the Hyper Module. There is a service bulletin that suggests replacing all of the 10uF surface mount electrolytics in several models. The symptom is usually what looks like a loss of sync, or zig-zag distortion in the image. It may be in one resolution and not another. It can sometimes make the set look like it has a convergence problem. In some sets, there is also a problem with the crystal resonators needing to be resoldered on the Hyper Module.
I have found that in addition to the problems with the 10uF caps, there are usually more bad surface mount electrolytics in the Hyper Module. I suggest ESR testing all of them and replacing all of the 10uF caps and any that test bad.
As an example, this is the list of capacitors that I replaced in one 65H82 in the Hyper Module:
(some caps shared the same label so location includes direction from label on board)
CZ52, C514, CX270, CX261, CX178, CX221, CX230, CX250, CX670, CX541, CX241
C404, C315, CY42, CY44
CX137, CX127, CX117, CX133, CX176 (right of label), CX176 (right and below label)
CV501, RZ68, CZ207, CX174, CX176 (directly below label)
Other sets have had different capacitors that have tested high in ESR. I do not recommend wholesale replacement, as many are good and it is very easy to damage the board even when using great care in removing the caps. The traces on some are not well bonded to the board. I recommend testing with an ESR tester and changing all of the ones that are bad, along with all of the 10uF caps.