The following is based on Using Airfoil with VLC.
When viewing a movie and streaming the audio track to a different computer, one can synchronize the audio by:
The relevant settings are in:
Input / Codecs → File Caching Audio → Audio desynchronization compensation
For example, on a 10Mbit ethernet local connection, the following settings perform fine:
Input / Codecs -> File Caching -> 6000ms Audio desynchronization compensation -> -2000ms
These settings are particular to a certain set-up so you can modify these values and figure out what works best for you.
When playing videos over the network with VLC, you may notice some stuttering along with the video appearing garbled for a short while. In order to work around that problem, the solution is to increase the VLC caches since the defaults are very small.