No, It's almost definitely not an interleave/preload/whatever mux-setting, as it works perfectly both if I split it up and if I just watch from the start. More likely (MOST likely, actually), some y2k-bug-writer in Microsoft said something on the lines of "Hell, who'd need a >2 Gig media file anyway?" and put a signed integer to hold filesize in the code. Or just accidentally wrote "int" and didn't bother checking if the default is signed or not. PTUI. Can someone please confirm the AC3 decoder (as is installed with audiofilters) is indeed Microsoft code? Because if *not* we might ask and thereby get this fixed. If it is, we might still get it fixed - we just need to ask more nicely ;-) Cheers.