HI, New to the site and first post I am having problems with my playback on my PC with HD files, I am using CoreAVC and AC3 filter. I am using them with Media Player Classic Home Cinema Edition. I tried putting my MPC in High and Above normal priority. I put CoreAVC and AC3 Filter as the Prefered Codec to use in External Filters. I had it once play FFX13 1080p Video (350mb for 2:43 of video), where the video was quick but the sound was cutting out as it couldnt keep up. Then now I dont know why the sound plays clear/smooth/and stays in line, but the video is slow and unable to keep up. I was going to use FFDShow but I read that it is more processor based where as CoreAVC was interlaceable. Of course Haali Media Splitter was installed with CoreAVC. My CPU is as follows, Intel P4 2600MHz Bus Speed 100 MHz Motherboard: Intel D865 PERL "black board edition" 2Gigz Ram, Video Card: ATI Radeon HD 2600 Pro AGP. Monitor: FLATRON L227WTG I was hoping to use more of my Video card power and processor to do the HD. I tried also msconfig and making it a very basic setup, shutting off my antivirus and anything I could think of, but then I didnt get video so i shut that off by accident I think unknowingly. I know it's vague or alot of information but any tweaks/ or anything could help. Oh I can play perfectly, Simpsons 1080P movie trailer fine, but playing a Blue Ray Rip 1080P sample file I got to try, (The Matrix first movie) the sound played fine but video was playing about half rate.