Sony KV-27S42 White Balance Failure

[MarkFromCA]

Hi, Thanks for the reply.

The "going for as long as I've had it" meant that it's been a persistent issue since I found the set.
I've done a semi-thorough pressure test on the chassis board but I haven't ruled out issues there.
The neckboard really does seem like the culprit. I already found cracked joints on a couple ground pins on the socket which I reflowed. I really should reflow off the tube just to make sure I did a proper job. A pressure test near the socket doesn't seem to cause a change too much. It's only around the areas of the connector to the chassis board and the crt drive IC (IC1751) where a pressure test seems to have an effect.
I'll try tapping the tube as well. I did a little exploratory tapping there and I didn't notice much.