Vfx 1.2.1 hangs after playing a few hours

After 3 hours of very smooth run, trying to load a video stopped Vfx play, with the well known windows message "Vfx had encountered an error... send ... don't send"
The video itself was ok, as it loaded perfectly after Vfx restart.
It ran ok for another 3 hours, but with less clips (longer ones) played.
This reminds of a similar issue with DVS PRO 7 video function : unlike Vfx it was using the PC's codecs instead of its own, and, as i use ffdshow, i could see a new instance of the ffdshow audio decoder loaded with each clip, and never unloaded... until crash.
Maybe there's still this kind of not freed structures in Vfx now, but unseeable as it's internal codecs...
The video itself was ok, as it loaded perfectly after Vfx restart.
It ran ok for another 3 hours, but with less clips (longer ones) played.
This reminds of a similar issue with DVS PRO 7 video function : unlike Vfx it was using the PC's codecs instead of its own, and, as i use ffdshow, i could see a new instance of the ffdshow audio decoder loaded with each clip, and never unloaded... until crash.
Maybe there's still this kind of not freed structures in Vfx now, but unseeable as it's internal codecs...