HD Video Playback Freezing/Stuttering Over Strong Wifi Connection

[IriDium]

As a first guess - without asking for too many questions - the RPi is only 10baseT even on Ethernet - Wifi is still going to be a lot less because of overheads. I don't know of anyone who has a "good" wifi setup for streaming HD.

Check CPU consumption first. Then try a Cat5 and see if that improves things.

First guess: you're trying to do something that the RPi cannot handle.

If none of that works,

Post xbmc.log, output from dmesg, "vmstat 5,20" and a screenprint of the "movie" playing with OSD - Type O when the movie is playing.

I think you will find that wifi is not too good for HD streaming.