Fedora X86/64bit :: 14 Cannot Play More Than 1 Multicast Stream

I have a project to run simultaneously up to 8 video streams, from a pool of about 100 multicast cameras, and display them on 4 monitors. The PC I am using is a brand-new dual CPU 4-core Intel Xeon E5620 2.40GHz, Intel S5520SCR motherboard, 8GB memory and nvidia Quadro NVS 450 graphics. It's running Fedora 14 64-bit and outputs on 2x2 LCD monitors using Xinerama. So far, so good.

Playing a single video stream from any camera works fine. The problem is that, when I open a 2nd media player window with the purpose of playing other camera, all those two video windows play a single stream. It doesn't matter which camera stream I opened first, as soon as I open a 2nd stream, both windows show the same stream (either the first, or the second, at what seems to be a random choice). Further, a 3rd or a 4th video window will also play the same stream. In other words, one stream sort of "contaminates" all the other streaming windows to play that particular stream only. The problem remains the same even when the following changes are applied:

- graphics driver: nvidia or nouveau;
- video player: vlc or mplayer;
- number of active monitors: 4, 2 or 1.

I am really puzzled because, on the same computer, Windows XP SP3 32-bit runs beautiful. I can smoothly play up to 12 video streams and some computer applications, simultaneously. I cannot believe that an obsolete OS such as Windows XP can outperform by a long shot Fedora 14 64-bit in video streaming projects. Just doesn't make sense.

Note: I have also tested Windows 7 64-bit, it also runs multiple video streams in parallel without any problems, but Win 7 has issues that XP is free of (such as graphics output glitching every few seconds).