Here is as quick a demo I could throw together which still meets my minimum quality requirements.

Opening a BIAB .mgu/.sgu file in BIAB VST in Reaper should be a simple as it can get. So take a look at my setup and see if you notice anything different from yours.



BIAB – 2025, Reaper (current), i7-12700F Processor, 32GB DDR4-3200MHz RAM, 1TB WD Black NVMe SSD, 2TB WDC Blue SSD, 1TB WD Blue, 2 TB SK NVMe, 6 TB External, Motu Audio Express 6x6