Mitsubishi CS-3506R PIP Beyond capacitors.....?

Hi, I have read a bunch of posts about the capacitors on circa 1990s Mits but this set is different from most of the posts I've read. This one has the 930B436 PIP (no bypass?) which does NOT have the surface mount caps and I've replaced just about all of the electrolytics in the set, I think I only have a few BP I can still replace. I have been battling the inverted video (no luma high chroma) on my set now for about 6 months and it seems to get better for 30 days at a time. Since the failures started I have also had another symptom which is a fairly loud audible buzz not from the speakers, but from the neck of the picture tube. I have found that if you swith the channel back and forth several times you can get something to sync and the buzz goes away. Reseting the power also seems to work sometimes. On my last round of capacitors (about 30) I again have a great picture but I still get that buzz intermittently. I have a few areas where the traces were compromised by the acid and I've had to make repairs but everything seems sound. I read on a couple of posts about the neck of the picture tube actually cracking which concerns me. This set came to me used with a vertical problem (fixed with 5 capacitors) and I only have about $50 in caps in it plus the picture is great when it works, so I definately want to get it fixed. For anyone reading this take the time and check ALL of the capacitors as in every section there have been many "fishy" caps if not just plain gunk leakin'! The condition of some of these caps was so bad, it's surprising that the crazy thing could run at all. If anyone has any tips to get rid of this buzz for good I sure would appreciate it. Thanks!