Tony,

I downloaded the files and was unable to replicate your issue. The first three played fine. The Notes Norton suggested it couldn't locate #8BTROK2.STY and substituted ZZJAZZ.STY (as expected). I had to change the Drums on this song to MIDI Drums. It too played fine using all MIDI tracks.

To prove it was definitely using external MIDI, I even powered off the Ketron SD2 while the song was playing and all sound stopped, and started again after powering the unit on again.

I notice that Jeff can reproduce your issue, so I hope that's good (in some sort of way?)

Could this be related in some way to the initialization of certain external devices, e.g. non GM MIDI compliant equipment?

BIAB & RB2024 Win.(Audiophile), Sonar Platinum, Cakewalk by Bandlab, Izotope Prod.Bundle, Roland RD-1000, Synthogy Ivory, Kontakt, Focusrite 18i20, KetronSD2, NS40M Monitors, Pioneer Active Monitors, AKG K271 Studio H'phones