i am assuming ac3-filter is the problem.on some h264 movies my amp reports a -27db dialogue normalisation,and so the volume level drops a lot.
this never happens on discs.
the weird thing is that it happens after having the pc for a few weeks.this is my third one.
i am using vista64 this time and was using vista32 on the earlier 2.
i am not really pc savvy but have friends and family who are and cant get round this.
when it started happening on this machine i tried doing a restore to a point a few days earlier but it did not help.