Well I've got some vids that I'm watching, and I notice that when I skip through them (to check if they all work correctly), the video plays very quickly as if on fast forward. The duration of this is different depending on the amount that I skip. Let's say I start at 0:01 seconds and decide to skip to 0:15. The "fast forward" last a lot longer than if I were to skip from 0:01 to 0:03. I've tested this on several different videos (eg, different animes/shows or films) and it seems that the "fast forward" duration differs (some vids don't even have it). I was wondering if there was a way to fix it up or at least lessen the duration.

Oh sorry, was using Media Player Classic

Before I get you to start examining your video codecs and such, I'd like to ask a few questions. Did this happen all of a sudden when for a long time it has never happened before? Or was this always a problem and you were just curious?

I would say it's the former

When was the last time you updated your codecs? New encodes can play havoc with older codecs.

Er, I just got CCCP and have been using it since like April or something

Well aside from telling you to clean your computer up and making sure you have at least 20% of your HDD free, I don't see how I can help you. Note that it could also be a hardware problem but I can't tell over the internet.

I've been poking around, and I noticed that all the vids which have the issue are all of those that I've changed file extensions (ie, mp4 to avi)
I've dug up an original, converted it and it seems to work fine (although I've only tried it on one vid so far). Guess being lazy and not wanting to waste time converting doesn't pay off.

This won't happen With VLC Media Player. It's literally the BEST media player to date with all its codecs in tact, and it can play virtually any media format, so you don't have to convert anything. Windows could learn from them.

W-what happened to her EYES!?

Aha, Nice one. But That was only true months & years ago. They fix bugs all the time.

Unlike other media players where they didn't really have those issues in the first place if you don't go out of your way to break it.

For Example?

Media Player Classic. Or KMPlayer (I do not endorse this though). The only time I've had problems was because encodes were s*** and that was fixed with a codec update.