I have always used either my keyboard and recently a foot switch to start BIAB and I have done this both a soft synth and now an external synth. If I remember correctly I was never able to rempove the delay at the start with a soft sythn no matter what I did but there is no problem with an external synth. Sometimes the soft synth start delay was very short but very irritating.

Whenever BIAB won't stsrt when you want it to just look at BIAB's keyboard. If the keyboard keypress shows up then BIAB should start. If it doesn't show up then the first thing I do is open "Opt/MIDI audio driver setup" and check that the midi input driver is set correctly. Sometimes, and I don't understand this, just opening and closing this audio driver setup window without changing anything resets the driver, the keyboard presses show up and BIAB will start.

Tony