As an update, I spoke to the Live Chat and in order to get close to syncing, I had to set both Reaper and BIAB properties to Run As Admin (Windows 10).

Although this got me very close, I later found I need to have Reaper's Play cursor starting on Bar 2 (with the Reaper's Start Measure set to 1) and when I hit Play on Reaper, BIAB immediately jumps to Bar 2 and stays in sync. At the end of the BIAB Song, both will loop to Bar 1 and stay in sync for multiple loops. There does seem that BIAB VST is late by a 1/8 note or so, especially noticeable on very slow-tempo songs.

However, if I have Reaper's play cursor at Bar 1 and press Play, BIAB starts out of sync and the BIAB Sync Bar Offset just makes it worse so it is set to 0.

Not the end of the world for what I need but still not ideal.


Last edited by gwp99; 07/10/23 03:45 PM.