if you mean odyssey then call it by name, aros owb is a completely different browser with a few years older webkit core.
what you refer to is odyssey acinerella interface to ffmpeg implemented via morphos glue interface (a single c file afair). so far i gather it has been known to be problematic on i386 abi vo in the past. i know it is problematic/doesnt really work with i386 abi v1 on my current odyssey compiles. it may be whatever, as far as im concerned, a bug in that code or too old version of ffmpeg it is linked against, because the standards have changed in the mean time. it seems morphos team is updating that part (i see pirus commits to acinerella) but they keep their changes closed. also someone here was attempting to update that part on their own, particularly for i386, but the approach has hit the wall it seems, as there is no further news about it.
i have been looking to update it myself. but i couldnt compile a working solution. it is too difficult for me.