I've had this problem for a long time, and I have no idea why. It doesn't always happen, but when it does it can be rather annoying. Sometimes, Blockland will just run a tiny bit faster than is normal, causing me serious rubberbanding issues in multiplayer. Usually the symptoms can be resolved with clientcmdtimescale(); set to 0.9 or 0.85, but that makes the in-game sounds noticeably slower. And besides, it'd be nice to know why it even happens in the first place.