b22d08eca6
Positive offsets still delay the whole mix via the delay line (lip-sync fix); negative offsets now ARM once at StartLive and drop |N| ms off the pipe's write head so audio events land earlier when audio runs BEHIND video. Slider relabeled AUDIO SYNC, Min −500, locked while live/recording (IsEditMode). LayoutStore and VM clamp to −500..500. OBS reference for eat-the-head negative sync: https://obsproject.com/kb/obs-studio/buffering-time (negative sync values pull audio earlier by discarding buffered player audio). Test: StartLive_NegativeOffset_AdvancesAudio_ByDroppingTheStreamHead (6x0.9 head must be eaten before 0.2 bed reaches the wire).