Some of the threads mentioned a problem with the Chinese manufactured toroidal core transformers, although that appears to not be your issue, however, looking at the photos, all of the electrolytics (and probably more) seems to come from China or similar. I would definitely be replacing all of those large value caps. They are all the same age as the crook one that you already identified. I'll bet if you measure them (out of circuit) they'll be out of tolerance.
My 2 cents, anyway...


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