I have been trying for some time now to stream video files from my PC to my 360 via the Windows Media Center app. I have followed the guidelines in several stickies and other forum posts to no avail. I can stream videos from apps like HBO, Netflix, Amazon, without any issue.
When I try streaming a video from my PC however, it begins and quite immediately becomes extremely pixelated. It usually freezes the picture on such a horribly pixelated image, where nothing can be made out, and the sound of the video file keeps playing as normal. If I let it go it may sometimes un-pixelate and run like normal for a few seconds, only to do it again. I have tried many different file types: AVI, MKV, MP4, MPG, WMV...and resolutions from SD to 1080p, all have the same results.
I can stream via my PS3 with no such problems, so I can't imagine the issue is with my network, computer, or internet connection.