MKV files suddenly not playing properly on VLC

[thekenoshakid]

I had been successfuly playing 720p MKV files on VLC for a few days. My computer was clearly powerful enough to do so. All of a sudden, the picture is horribly shaky/wavy with constant pixelation whenever an MKV file is played. Things are normal with AVI. I didn't change any settings or anything. Does anyone have any idea what could be going on?

[davexnet]

PC overheating? CPU maxed out ? (check Task Manager)
DO the same files that played good earlier still play OK now?

[thekenoshakid]

CPU usage does not go above 25%. Files that previously played perfectly are now wavy/shaky/pixelated to the point you can't recognize what's on the screen. Out of about 10 mkv files, there is one that still works, I don't know why. After my first post, I remembered that, in attempting to maximize picture quality, I messed around with "deinterlace", "deinterlace mode", "post-processing" and probably a few other things in the video settings in "preferences". However, I uninstalled and reinstalled VLC, and the problem persists. I find it really strange, since I had watched all these videos from beginning to end and there was no problem. I can't figure out if the problem is with VLC or my computer; although I can't imagine what would have happened to my computer between Saturday and today to cause this change. The only thing I did was watch an abundance of mkv videos.

[davexnet]

Somewhere in the VLC related shortcuts (eg. start button/programs/VLC) there is an item to set all preferences back to default.
CLose VLC, execute the reset and re-open VLC.

Which release of VLC are you using?

[thekenoshakid]

Yeah, you're right, and I'm a moron. I forgot I had been messing around in the Input and Codecs settings. I reset it and it's fine now. Funny uninstalling/reinstalling didn't help; but anyway, thanks for the help.

[davexnet]

Not a problem, glad you sorted it.

Often, when programs are uninstalled, these kinds of preferences, usually stored in the
HKEY_CURRENT_USER part of the registry are kept, so you can have your prefences back if you reinstall.
Some programs ask if you want to keep them or not.