Why is audio out of sync with video?

[DeloskyGA]

Newbie here. I'm trying to figure out why in some movies, and sometimes only in some tracks but not all, the audio is out of sync with the video. I thought initially it was because the DVDs were Standard/Widescreen double sided. But then after ripping Mission Impossible 2, the main movie track was fine, but the Special Feature clips all had audio out of sync.

Here are my system settings:
- HP ProBook 455 G1
- Windows 10, 64 bit, fully updated
- MKV v1.12.3
- HP DVD-RAM UJ8D8 Optical drive, Microsoft 10.0.17134.137 driver

Is this a form of my laptop? Or is this as easy as a setting within MKV to fine tune?

[Woodstock]

A lot depends on your player. There have been several discussions of this over on handbrake.fr, and certain players have timing issues with MKV files. Not always, but often enough to be a known issue.