Sudden problems - buffering, lockups and pixelation

I have been using Plex in my home for about 2+ years now with zero problems. I have 3 windows computers that have the Plex Media server on them, and two TV’s that have a Roku running Plex on them so I can watch videos on my TV. I’m a software engineer and media creator, so I’m good about keeping the media servers up to date with the latest version and doing the same on the Roku’s.

Just recently, Plex has started to act strangely. It will be humming along just fine, watching a movie, when all of sudden, various things may happen:

  1. The movie will freeze and then begin buffering at insanely slow speeds. Usually it hits a plateau right around 33% where you can literally go get a cup of coffee. If you have the patience and wait about 15 minutes, it will eventually start to move and slowly creep back up to 100%, at which point the video plays for a few seconds and then freezes entirely, never to recover. (Unless you reboot stuff)

  2. Sometimes it freezes and then starts to pixelate badly. The screen gets filled with pink/white/black/other squares and the sound makes loud scratching noises. It does not recover from this, reboot

  3. It just plain freezes. Reboot.

I’ve tried:

  1. Making sure the media servers are up to date
  2. Rebooting the servers and doing basic cleanup on them (removing temp files and dead registry entries)
  3. Updating and rebooting the Roku’s
  4. Rebooting the modem and router
  5. Drinking alcohol and weeping like a baby

The computers, rokus, network and all that work just fine outside of this problem. To be fair, I use my laptop as the main media server and I’m not sure if the other two are experiencing the problem. The laptop in question is my main machine which I use to code development and media creation, so it has a lot of stuff installed. But then again, as I said, I’ve been using this same machine in it’s same basic state for 2+ years now with no problems as far as Plex is concerned. I saw some notes in the support FAQ about DLL’s causing problems, but I’m seeing the symptoms they mention, such as the media server crashing and closing, etc.

I’m open to ideas. Is anyone else experiencing these issues? Any thoughts on what to try?