Thanks, JazzMammal,

I previously tried extending it to 8 bars, and this time it died at the end of the second song.

I've just tried 16 bars, and BIAB died at the end of the sixth song.

I've generated and then frozen all the RT-containing songs before saving them, so I don't think that generation time should really be the issue. When this happened to me that last time (in 2010) I tested it out on two computers with widely differing resources (4 times the RAM and a much faster processor), and found they both got stuck at the same point.

My purpose here isn't to find a way of playing four bars of each piece with JukeBox (a pretty useless activity, I have to admit!), but to point out that I can repeatedly cause BIAB to hang.

I don't think a program should hang like this - particularly one which is used for live performance - and if BIAB is indeed "allow[ing] a song ... to start playing before the song has finished generating" it should be able to deal more elegantly with the consequences.

When I did some semi-professional programming in years gone by, I was delighted to be informed of reproducible problems with my code, as they often revealed problems in sections of code I would never have thought of checking, and which were causing other obscure problems,