Strange CRT behavior

[Datana]

I've been using a 19" Trinitron-based CRT as my monitor for the past few years, and lately it's been showing some odd behavior:

• A high-pitched whine occurs whenever the refresh rate goes above 85 Hz (the monitor supports far higher rates than this at the resolutions I'm using); while this is tolerable, it's extremely annoying. I can sometimes get it to stop by thwacking it on the side.
  
  Text is starting to lose focus. It's fuzzy and becoming increasingly hard to read. I've tried adjusting convergence and moire settings, but changing anything from the defaults makes things worse. I've been getting around this by simply decreasing resolution and increasing text size, but don't really like the reduced desktop area.
  
  A red/green/blue interference pattern has started to appear on the screen at all resolutions and refresh rates -- this looks like a series of three sine waves (one for each color) moving from top to the bottom of the screen, with maxima and minima at the left and right edges of the screen. The pattern is so constant that I'm beginning to worry if it might cause burn-in.

I'm suspecting that this screen is dying, but was wondering if anyone here has any ideas on how to stave this off.

[Sharp-kun]

Tried a degauss?

[Datana]

Tried a degauss?

One of the first things I did. I've also tried resetting to factory defaults and setting the color return, but none of these seem to do anything.

[Xon]

Sounds like it is dieing.

It might be posible to get it repaired, but thats only worth it if it is still under warranty. Which is probably likely, normally there is a fairly long warranty on monitors.

[Dalton]

Hm. Sounds like the picture tubes are out of alignment or dying. You'll probably need a new monitor soon.

[Jawawithagun]

Focussing coil shaken loose?

[Shadowhawk]

You can fix the blurry text problem easily enough by taking the cover off the monitor (Be careful! There are lethal amps going through there! Don't work on it while you're home alone, just in case), finding the Focus potentiometer, and tweaking it. I've had to do that twice with my monitor in the past couple years.
The weird divergance thing you're getting might also be solved by tweaking other potentiometers squirreled away inside the cover.

[Datana]

You can fix the blurry text problem easily enough by taking the cover off the monitor (Be careful! There are lethal amps going through there! Don't work on it while you're home alone, just in case), finding the Focus potentiometer, and tweaking it. I've had to do that twice with my monitor in the past couple years.
The weird divergance thing you're getting might also be solved by tweaking other potentiometers squirreled away inside the cover.

Thanks! This fixed both the weird buzzing and the focus issues. I'm still getting divergence problems, though. I managed to find the entire service manual after some extensive Googling, which I'm searching through for a solution now. The basic diagnostic requires some proprietary software, but there might be something else tweakable.

[Vertigo1]

I'd start looking for a replacement if I were you. When the tube starts acting up, the monitor is more than likely going south.